EMC VSPEX WITH EMC XTREMSF AND EMC XTREMSW CACHE

Transcription

1 DESIGN GUIDE EMC VSPEX WITH EMC XTREMSF AND EMC XTREMSW CACHE EMC VSPEX Abstract This describes how to use EMC XtremSF and EMC XtremSW Cache in a virtualized environment with an EMC VSPEX Proven Infrastructure for VMware vsphere or Microsoft Hyper-V. This also illustrates how to choose XtremSF and allocate XtremSW Cache resources following best practices for maximum effectiveness, and use all the benefits that XtremSW Cache offers. May 2013

2 Copyright 2013 EMC Corporation. All rights reserved. Published in the USA. Published May EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice. The information in this publication is provided as is. EMC Corporation makes no representations or warranties of any kind with respect to the information in this publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license. EMC 2, EMC, and the EMC logo are registered trademarks or trademarks of EMC Corporation in the United States and other countries. All other trademarks used herein are the property of their respective owners. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache Part Number H EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

3 Contents Contents Chapter 1 Introduction 9 Purpose Business value Scope Audience Terminology Chapter 2 Before You Start 13 Deployment workflow overview Essential reading VSPEX Solution Overviews VSPEX Implementation Guides VSPEX Proven Infrastructures Chapter 3 Solution Overview 17 Introduction EMC VSPEX Proven Infrastructure EMC XtremSW Cache: The business case Introduction to XtremSF and XtremSW Cache XtremSF XtremSW Cache Business benefits of XtremSF and XtremSW Cache XtremSF XtremSW Cache XtremSW Cache features Solution architecture How XtremSW Cache works XtremSW Cache in a virtualized environment Chapter 4 Solution Design Considerations and Best Practices 33 Overview VSPEX environments that can benefit from XtremSW Cache XtremSF card selection Overview Design best practices EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 3

4 Contents Virtualization design considerations Overview Sizing recommendations XtremSW Cache placement considerations Overview Design best practices VMware considerations Overview Design best practices Hyper-V considerations Overview Design best practices Chapter 5 XtremSW Cache Solution for Applications 45 Overview Architecture of XtremSW Cache deployment on VMware Architecture of XtremSW Cache deployment on Hyper-V XtremSW Cache for SQL Server OLTP database Overview Benefits of XtremSW Cache in a SQL Server OLTP environment Best practices Use case design and deployment Configuration of XtremSW Cache in the VMware environment Test results XtremSW Cache for Exchange Server Overview Benefits of XtremSW Cache in an Exchange environment Best practices Use case design and deployment Configuration of XtremSW Cache in the VMware environment Test results XtremSW Cache for SharePoint Overview Benefits of XtremSW Cache in a SharePoint environment Best practices Use case design and deployment Configuration of XtremSW Cache in the VMware environment Test results XtremSW Cache for Oracle OLTP database EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

5 Contents Overview Benefits of XtremSW Cache in an Oracle environment Best practices Use case design and deployment Configuration of XtremSW Cache for Oracle in a VMware environment Test results XtremSW Cache for private cloud Overview Benefits of XtremSW Cache in a private cloud environment Best practices Use case design and deployment Configuration of XtremSW Cache for a private cloud in the VMware environment. 76 Test results Chapter 6 References 79 EMC documentation Other documentation Links Appendix A Ordering Information 83 XtremSF and XtremSW Cache ordering information EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 5

6 Contents Figures Figure 1. VSPEX Proven Infrastructure Figure 2. I/O gap between the processor and storage subsystems Figure 3. XtremSW Cache data deduplication Figure 4. XtremSW Cache data deduplication architecture overview Figure 5. Split-card mode used for SQL Server configuration Figure 6. Read Hit example with XtremSW Cache Figure 7. Read Miss example with XtremSW Cache Figure 8. Write example with XtremSW Cache Figure 9. XtremSW Cache implementation in a VMware environment Figure 10. XtremSW Cache in a VMware environment Figure 11. XtremSW Cache in a Hyper-V environment Figure 12. XtremSW Cache use cases Figure 13. Comparison between SLC and MLC Flash cell data storage Figure 14. XtremSW Cache configuration using EMC VSI plug-in Figure 15. XtremSW Cache implementation in VMware environment for VSPEX Figure 16. XtremSW Cache implementation in Hyper-V environment for VSPEX Figure 17. Figure 18. Figure 19. Architecture of the VSPEX Proven Infrastructure for XtremSW Cache deployment on VMware Architecture of the VSPEX Proven Infrastructure for XtremSW Cache deployment on Hyper-V Architecture design for XtremSW Cache enabled SQL Server virtual environment Figure 20. SQL Server AlwaysOn XtremSW Cache deployment Figure 21. Performance boost after enabling XtremSW Cache Figure 22. Architecture design for XtremSW Cache-enabled Exchange virtual environment Figure 23. XtremSW Cache deployment for Exchange 2010 on vsphere Figure 24. Enabling data deduplication on the XtremSW Cache device Figure 25. Cold cache start post migration warning Figure 26. Figure 27. EMC XtremSW Cache VSI-plug-in for virtual machine migration wizard Exchange 2010 performance with XtremSW Cache and LoadGen workload Figure 28. XtremSW Cache statistics with data deduplication Figure 29. Figure 30. Figure 31. Exchange server CPU utilization with XtremSW Cache data deduplication Exchange server disk latencies with XtremSW Cache data deduplication Exchange database LUN performance with XtremSW Cache data deduplication EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

7 Figure 32. Contents Architecture design for XtremSW Cache enabled SharePoint environment Figure 33. XtremSW Cache deployment for SharePoint 2010 on vsphere Figure 34. Content database latency dropped after enabling XtremSW Cache Figure 35. Full crawl performance improved after enabling XtremSW cache Figure 36. Architecture design for XtremSW Cache enabled Oracle 11g R2 environment Figure 37. XtremSW Cache deployment for Oracle 11g R2 on vsphere Figure 38. OLTP TPM improvement Figure 39. Architecture design for XtremSW Cache-enabled private cloud environment with multiple applications Figure 40. Deduplication statistics for SQL Server OLTP Tables Table 1. Terminology Table 2. Deployment process: XtermSF and XtremSW Cache overlay on VSPEX Proven Infrastructure Table 3. Performance characteristics of selected XtremSF cards Table 4. SLC and MLC Flash comparison Table 5. Recommended cache for each application Table 6. Performance data with OLTP load Table 7. XtremSW Cache deployment in a private cloud environment Table 8. Performance summary for the private cloud environment EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 7

8 Contents 8 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

9 Chapter 1: Introduction Chapter 1 Introduction This chapter presents the following topics: Purpose Business value Scope Audience Terminology EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 9

10 Chapter 1: Introduction Purpose Business value Scope EMC VSPEX Proven Infrastructures are optimized for virtualizing business-critical applications. VSPEX provides partners with the ability to plan and design the virtual assets to support applications such as Microsoft SQL Server, Microsoft SharePoint, Microsoft Exchange, and Oracle Database among others on a VSPEX Private Cloud. The EMC VSPEX with EMC XtremSF and EMC XtremSW Cache solution provides partners with a server-based caching solution that reduces application latency and increases throughput. This solution runs on VMware vsphere or Microsoft s Hyper-V virtualization layer, backed by the highly available EMC VNX family of storage systems. The computing and network components, while vendor-definable, are designed to be redundant and are sufficiently powerful to handle the processing and data needs of the virtual machine environment. This describes how to design XtremSW Cache for a VSPEX Proven Infrastructure and includes best practices and the results of use case testing. IT administrators running applications with heavy input/output (I/O) loads are often challenged to improve performance, while continuing to minimize the cost of the supporting IT systems. These I/O sensitive applications are typically limited by storage latency and response times. XtremSW Cache is intelligent caching software that uses server-based Flash technology to improve performance by reducing latency and accelerating throughput for dramatic application performance improvement. XtremSW Cache accelerates read performance by putting the data closer to the application. It also protects data by using a write-through cache to the networked storage array to deliver persistent high availability (HA), integrity, and disaster recovery. XtremSW Cache, coupled with array-based EMC FAST software, creates the most efficient and intelligent I/O path from the application to the datastore. The result is a networked infrastructure that is dynamically optimized for performance, intelligence, and protection for both physical and virtual environments. This is an overlay solution that describes how to design and deploy XtremSW Cache on a VSPEX Proven Infrastructure for VMware vsphere or Microsoft Hyper-V. Furthermore, this guide illustrates best practices and recommendations for using XtremSW Cache to improve the performance of virtualized applications running on a VSPEX Proven Infrastructure. 10 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

11 Chapter 1: Introduction Audience This guide is intended for qualified EMC VSPEX partners. The guide assumes that VSPEX partners who intend to deploy XtremSF and XtremSW Cache on respective applications are: Qualified to sell and implement the application(s) that will be used in conjunction with the XtremSW Cache solution Qualified by EMC to sell, install, and configure the EMC VNX family of storage systems Certified for selling VSPEX Proven Infrastructures Qualified to sell, install, and configure the network and server products required for VSPEX Proven Infrastructures Trained in and familiar with EMC s XtremSF hardware and XtremSW Cache software Readers must also have the necessary technical training and background to install and configure: EMC VSPEX Server virtualization solutions for VMware vsphere or Microsoft Hyper-V, depending on the hypervisor in use Windows Server 2012 with Hyper-V or VMware vsphere as the virtualization platforms External references are provided where applicable and EMC recommends that readers are familiar with these documents. For details, see Essential reading. Terminology Table 1 includes the terminology used in this guide. Table 1. Terminology Term Cache page size CSV DAS DSS IOPS NFS PCIe Definition The smallest unit of allocation inside the cache, typically a few kilobytes in size. The default XtremSW Cache page size is 8 KB. Cluster-shared volume. A Windows Server clustering feature that enables multiple clustered virtual machines to use the same logical unit number (LUN). Direct-attached storage. Decision support system. Input/output operations per second. Network File System. Peripheral Component Internet Express. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 11

12 Chapter 1: Introduction Term tempdb VHDX VMDK Working set XtremSF XtremSW XtremSW Cache Definition Refers to a system database used by Microsoft SQL Server as a temporary working area during processing. Hyper-V virtual hard disk format. VMware virtual machine disk format. The frequently accessed data that is likely to be promoted to XtremSW Cache. EMC Peripheral Component Internet Express (PCIe) Flash cards with industry-leading performance. EMC software for server-side caching on PCIe Flash cards. EMC server Flash-caching software as part of XtremSW software suite. 12 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

13 Chapter 2: Before You Start Chapter 2 Before You Start This chapter presents the following topics: Deployment workflow overview Essential reading EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 13

14 Chapter 2: Before You Start Deployment workflow overview EMC recommends that you refer to the process flow in Table 2 to design and implement your XtremSF and XtremSW Cache overlay on the VSPEX Proven Infrastructure. Table 2. Deployment process: XtremSF and XtremSW Cache overlay on VSPEX Proven Infrastructure Step Action Reference 1 Review the XtremSW Suite products and features. EMC documentation 2 Determine if the XtremSW Cache solution is appropriate for your application. 3 Select and order the right VSPEX Proven Infrastructure. 4 Select the required XtremSW Cache hardware and determine where to place the cards. Solution Design Considerations and Best Practices VSPEX Proven Infrastructures XtremSW Cache Solution for Applications 5 Deploy and test your virtualized applications VSPEX Implementation Guides Essential reading EMC recommends that you read the following documents, available from the VSPEX space in the EMC Community Network or from the VSPEX Enablement Center. VSPEX Solution Overviews VSPEX Implementation Guides Refer to the following VSPEX Solution Overview documents: EMC VSPEX Server Virtualization for Midmarket Businesses EMC VSPEX Server Virtualization for Small and Medium Businesses Refer to the following VSPEX Implementation Guides: EMC VSPEX for Virtualized Microsoft Exchange 2010 with Microsoft Hyper-V EMC VSPEX for Virtualized Microsoft Exchange 2010 with VMware vsphere EMC VSPEX for Virtualized Microsoft SharePoint 2010 with Microsoft Hyper-V EMC VSPEX for Virtualized Microsoft SharePoint 2010 with VMware vsphere EMC VSPEX for Virtualized Microsoft SQL Server with Microsoft Hyper-V EMC VSPEX for Virtualized Microsoft SQL Server with VMware vsphere EMC VSPEX for Virtualized Oracle Database 11g OLTP 14 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

15 Chapter 2: Before You Start VSPEX Proven Infrastructures Refer to the following VSPEX Proven Infrastructures: EMC VSPEX Private Cloud VMware vsphere 5.1 for up to 100 Virtual Machines EMC VSPEX Private Cloud VMware vsphere 5.1 for up to 500 Virtual Machines EMC VSPEX Private Cloud Microsoft Windows Server 2012 with Hyper-V for up to 100 Virtual Machines EMC VSPEX Private Cloud Microsoft Windows Server 2012 with Hyper-V for up to 500 Virtual Machines EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 15

16 Chapter 2: Before You Start 16 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

17 Chapter 3: Solution Overview Chapter 3 Solution Overview This chapter presents the following topics: Introduction EMC VSPEX Proven Infrastructure EMC XtremSW Cache: The business case Introduction to XtremSF and XtremSW Cache Business benefits of XtremSF and XtremSW Cache XtremSW Cache features Solution architecture EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 17

18 Chapter 3: Solution Overview Introduction This can help customers to deploy a simple, efficient, and flexible VSPEX Proven Infrastructure with XtremSF and XtremSW Cache solution. The guidance applies to all VSPEX Proven Infrastructures unless specifically stated otherwise. This chapter provides an overview of VSPEX Proven Infrastructure, XtremSF and XtremSW Cache, and the key technologies used in the XtremSF and XtremSW Cache overlay for the VSPEX Proven Infrastructure. A VSPEX Proven Infrastructure includes servers, storage, network components, and application components that focus on small and medium business private cloud environments. The XtremSF and XtremSW Cache overlay provides latency reduction and accelerates throughput for dramatic application performance improvement. EMC VSPEX Proven Infrastructure VSPEX Proven Infrastructure, as shown in Figure 1, is a modular, virtualized infrastructure validated by EMC and delivered by EMC partners. VSPEX includes a virtualization layer, server, network, and storage, designed by EMC to deliver reliable and predictable performance. Figure 1. VSPEX Proven Infrastructure VSPEX provides the flexibility to choose network, server, and virtualization technologies that fit a customer s environment to create a complete virtualization solution. VSPEX delivers faster deployment for EMC partner customers, with greater simplicity and efficiency, more choice, and lower risk to a customer s business. 18 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

19 Chapter 3: Solution Overview EMC XtremSW Cache: The business case Since the latest servers have faster processors, there is a potential for a performance bottleneck in the storage layer. As processing capacity and workloads increase, the storage system is challenged to keep pace with growing I/O demands. The performance of the magnetic disk remains relatively flat while CPU performance improves 100-fold every decade, as shown in Figure 2. XtremSF Flash drives can help to close the gap. Figure 2. I/O gap between the processor and storage subsystems Flash technology can be used in different ways in the storage environment. EMC s architectural approach is to use the right technology in the right place at the right time. This includes using Flash in the following ways: In the storage array As an array-side cache As a server-side cache As a tier As the storage for the entire application Introduction to XtremSF and XtremSW Cache XtremSW Cache (formerly known as EMC VFCache) is the first step in EMC s long-term server Flash strategy, which delivers a server-side storage product featuring a combination of intelligent caching software XtremSW Cache and server-based Peripheral Component Internet Express (PCIe) Flash hardware XtremSF. XtremSW Cache software turns the XtremSF card into a caching device, to enhance the performance of a wide variety of critical transactional and decision support applications. XtremSW Cache can run with a wide variety of enterprise multilevel cell (emlc) and single-level cell (SLC) XtremSF Flash cards. For more information, see Appendix A: Ordering Information. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 19

20 Chapter 3: Solution Overview XtremSF XtremSW Cache XtremSF is single, low-profile server Flash hardware card that fits in any rack-mounted server within the power envelope of a single PCIe slot, available with a broad set of emlc and SLC capacities. It can be deployed: As local storage that sits within the server to deliver high performance In combination with XtremSW Cache server-caching software to improve network storage array performance, while maintaining the level of protection required by critical application environments XtremSW Cache is EMC server-caching software for Flash PCIe cards, which is used to populate XtremSF with data in order to use it as a cache. XtremSW Cache is designed to follow these basic principles: Performance: Reduce latency and increase throughput to dramatically improve application performance. Intelligence: Add another tier of intelligence by extending FAST array-based technology into the server. Protection: Deliver performance with protection by using the high availability and disaster recovery features of EMC networked storage. VSPEX partners can order XtremSW Cache software and XtremSF hardware through Channel Express. For ordering information, refer to Appendix A: Ordering Information. Table 3 shows the performance characteristics of some selected XtremSF cards. Table 3. Performance characteristics of selected XtremSF cards Measurement 550 GB emlc 2.2 TB emlc 350 GB SLC 700 GB SLC Read Bandwidth 1.36 GB/s 2.47 GB/s 2.9 GB/s 2.9 GB/s Write Bandwidth 512 MB/s 1.1 GB/s 756 MB/s 1.8 GB/s Random 4K Read IOPS 174K 343K 715K 712K Random 4K Write IOPS 49K 105K 95K 197K Random 4K Mixed IOPS 96K 206K 267K 411K Read Access Latency 87 µs 87 µs 50 μs 50 μs Write Access Latency 37 µs 30 µs 13 μs 13 μs 20 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

21 Chapter 3: Solution Overview Business benefits of XtremSF and XtremSW Cache XtremSF XtremSW Cache XtremSF delivers high performance with extremely high IOPS and low latencies. It enables applications to achieve memory-class performance without having to acquire additional memory, and high storage capacity with a small footprint. The XtremSF family of server-based PCIe Flash cards offers customers with the following benefits: Leading performance: XtremSF Flash devices are proven to deliver a record 1.13 million IOPS in a standard form factor an achievement unmatched in the industry. The XtremSF device s next-generation design delivers twice the throughput of other offerings in the market to enhance realworld workloads in Web-scale and other applications. Unmatched flexibility: The XtremSF Flash device is available in a broad range of emlc (from 550 GB up to 2.2 TB) and SLC (350 GB and 700 GB) capacities. In addition, when deployed with XtremSW Cache, XtremSF devices can be used as caching devices for accelerated performance with array protection for applications such as Oracle, Microsoft SQL Server, and Microsoft Exchange. New levels of efficiency: XtremSF Flash devices deliver the industry s lowest total cost of ownership (TCO) up to 58 percent better TCO than other offerings. All XtremSF products are standard half-height, half-length, 25W PCIe cards, providing the highest storage capacity with the smallest footprint for maximum performance, best density, and lowest power consumption reducing CPU utilization by up to 50 percent. XtremSW Cache delivers the following major benefits: Provides performance acceleration for read-intensive workloads As a write-through cache, enables accelerated performance with the protection of the back-end, networked storage array Provides an intelligent path for the I/O and ensures that the right data is in the right place at the right time In split-card mode, enables you to use part of the server Flash for cache and the other part as DAS for temporary data By offloading Flash and wear-level management onto the PCIe card, uses minimal CPU and memory resources from the server Achieves greater economic value when data deduplication is enabled by providing an effective cache size larger than the physical size, and longer card life expectancy Works in both physical and virtual environments Integrated with EMC Virtual Storage Integrator (VSI) plug-ins for vsphere makes it simple to manage and monitor XtremSW Cache in a VMware environment Works in Active/Passive clustering environments EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 21

22 Chapter 3: Solution Overview Works with VMware live migration Provides a highly scalable performance model in the storage environment XtremSW Cache features Server-side Flash caching for maximum speed Write-through caching for total protection Application and storage agnostic XtremSW Cache software caches the most frequently referenced data on the serverbased PCIe card XtremSF, thereby putting the data closer to the application. The XtremSW Cache caching optimization automatically adapts to changing workloads by determining which data is most frequently referenced and promoting it to the server Flash cache. This means that the hottest (most active) data automatically resides on the PCIe card in the server for faster access. XtremSW Cache accelerates reads and protects data by using a write-through cache to the storage array to deliver persistent high availability, integrity, and disaster recovery. XtremSW Cache is transparent to applications, so no rewriting, retesting, or recertification is required to deploy XtremSW Cache in the environment. XtremSW Cache works with any storage array in the enviornment. Regardless of the vendor or type of the storage, it works seamlessly to improve the performance of the storage array. XtremSW Cache offloads much of the read traffic from the storage array, which allows it to allocate greater processing power to other applications. While one application is accelerated with XtremSW Cache, the array s performance for other applications is maintained or even slightly enhanced. Integrated with vsphere Integrated with Hyper-V Minimum impact on system resources XtremSW Cache enhances both virtulized and physical environments. Integration with VSI plug-ins for vsphere makes it simple to manage and monitor XtremSW Cache. XtremSW Cache works seamlessly with the Windows Hyper-V host and the virtual machines that build on top. XtremSW Cache does not require a significant amount of memory or CPU cycles because all Flash and wear-level management is done on the PCIe card and does not use server resources. Unlike other PCIe solutions, there is no significant overhead from using XtremSW Cache on the server resources. XtremSW Cache creates the most efficient and intelligent I/O path from the application to the datastore, which results in an infrastructure that is dynamically optimized for performance, intelligence, and protection for both physical and virtual environments. 22 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

23 Chapter 3: Solution Overview Data deduplication Currently, EMC is the only vendor to provide customers with a deduplication option on a server cache Flash card. Deduplication can provide the following benefits: Better cost per gigabyte: Using effective cache size, which is larger than the physical cache size Longer card life expectancy: Reduction in the number of write operations to the Flash card resulting in lower wear out Data deduplication can eliminate redundant data by storing only a single copy of identical chunks of data, while enabling this data to be referenced. As shown in Figure 3, when deduplication is enabled, only one copy of data is actually stored in XtremSW Cache. With some additional memory space for pointers, the data that can be cached increases dramatically. Figure 3. XtremSW Cache data deduplication Data deduplication uses server memory to process the deduplication function to maximize the capacity of XtremSW Cache. You can enable or disable this functionality as needed. Figure 4 shows the deduplication architecture in XtremSW Cache. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 23

24 Chapter 3: Solution Overview Figure 4. XtremSW Cache data deduplication architecture overview Active/Passive clustering support Multiple cards per server Orchestrated VMware vmotion XtremSW Cache supports the Active/Passive clustering of the native operating system (OS). Configuring the XtremSW Cache cluster scripts ensures that stale data is never retrieved. The scripts use cluster management events to trigger a mechanism that purges the cache. The XtremSW Cache-enabled Active/Passive cluster can ensure data integrity while accelerating the application performance. If necessary, you can install multiple XtremSF cards on a single server and configure them as cache devices to improve application performance. Each source device can be associated only with one cache card. XtremSW Cache supports live migration for VMware. During the migration process, the virtual machine is operational and the cache is purged with a temporary I/O performance impact. Orchestrated VMware vmotion can be easily initiated from the XtremSW Cache VSI plug-in while the virtual machines are up and running. This live migration offers easier environment maintenance along with business continuity. XtremSW Cache is the only certified solution that is interoperable with vmotion standards and listed in the VMware Compatibility Guide. XtremSW Cache support for orchestrated VMware vmotion automatically removes XtremSW Cache devices on the virtual machine, deletes the cache on the local virtual device, and migrates the virtual machines to the target host. After migration, the cache device is recreated on the target host s XtremSW Cache card datastore with the 24 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

25 Chapter 3: Solution Overview same properties as those on the source host machine. The virtual machine on the target host has the same XtremSW Cache configuration as that on the source host after migration. Split-card mode support XtremSW Cache includes a unique software option that enables you to split the XtremSF card between the cache and the local storage. You can simultaneously use the card as a caching device for critical data and as a read-and-write storage device for temporary data. You can fully optimize your workload by adjusting caching or storage without having to change your card deployment. With this feature, both read and write operations from the application to the local storage are performed directly on the Flash capacity in the server. Since the data on the local Flash storage does not persist in any storage array, it is best used for ephemeral data only, such as the operating system swap space and temporary file space. Figure 5 shows an example of a use case for the split-card mode of XtremSW Cache. In a SQL Server, where the tempdb needs acceleration for both read and write operations but the database file only needs read acceleration, XtremSF can be configured so that part of the card can be used for the local storage as tempdb, and part of it can be used as a cache. However, there is a limitation in this configuration as vmotion is not viable when the tempdb storage is local. Figure 5. Split-card mode used for SQL Server configuration EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 25

26 Chapter 3: Solution Overview Solution architecture How XtremSW Cache works If the application I/O is for a source volume on which XtremSW Cache has not been enabled, then the XtremSW Cache driver is transparent to the application I/O and works as if there is no XtremSW Cache driver in the server I/O stack. In the following examples, the application I/O is assumed for a source volume which is being accelerated by XtremSW Cache. Read Hit example In this example, XtremSW Cache has been running for some time and the application working set has already been promoted into XtremSW Cache. The application issues a read request, and the data is present in XtremSW Cache. This process is called Read Hit, as shown in Figure 6. Figure 6. Read Hit example with XtremSW Cache The sequence of the steps in Figure 6 is: 1. The application issues a read request that is intercepted by the XtremSW Cache driver. 2. Because the application working set has already been promoted into XtremSW Cache, the XtremSW Cache driver determines that the data being requested by the application already exists in the XtremSW Cache. Therefore, the read request is sent to the PCIe XtremSF card rather than to the back-end storage. 3. Data is read from the XtremSW Cache and returned to the application. 26 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

27 Chapter 3: Solution Overview Read Hit provides all the throughput and latency benefits of XtremSW Cache to the application because the read request is fulfilled within the server rather than incurring latencies in going over the network to the back-end storage. Read Miss example In this example, the application issues a read request and the data is not present in XtremSW Cache. This process is called Read Miss, as shown in Figure 7. The data is not present in XtremSW Cache either because the card has just been installed in the server or the application working set has changed so that the application has not yet referenced this data. Figure 7. Read Miss example with XtremSW Cache The sequence of the steps in Figure 7 is: 1. The application issues a read request that is intercepted by the XtremSW Cache driver. 2. The XtremSW Cache driver determines that the requested data is not in XtremSW Cache and forwards the request to the back-end storage. 3. The data is read from the back-end storage and returned to the application. 4. Once the application read request is completed, XtremSW Cache driver writes the requested data to the XtremSF card. This process is called promotion. This means that when the application reads the same data again, it will be a Read Hit for XtremSW Cache, as described in the previous example. If all the cache pages in XtremSW Cache are already used, XtremSW Cache uses a least-recently-used (LRU) algorithm to write new data. If needed, the data that is least likely to be used in future is discarded first to create space for the new XtremSW Cache promotions. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 27

28 Chapter 3: Solution Overview Write example In this example, the application has issued a write request, as shown in Figure 8. Figure 8. Write example with XtremSW Cache The sequence of the steps in Figure 8 is: 1. The application issues a write request that is intercepted by the XtremSW Cache driver. 2. Since this is a write request, the XtremSW Cache driver passes this request to the back-end storage for completion. The data in the write request is written to the XtremSW Cache card in parallel. If the application is writing to a storage area that has already been promoted to XtremSW Cache, the copy of that data in XtremSW Cache is overwritten. Therefore, the application does not receive a stale or old version of data from the XtremSW Cache in response to future read requests. XtremSW Cache algorithms ensure that, if the application writes some data and then reads the same data later on, the read requests will find the requested data in XtremSW Cache. 3. Once the write operation is completed on the back-end storage, an acknowledgment for the write request is sent back to the application. The process of promoting new data into XtremSW Cache, as described in the previous two examples, is called cache warm-up. Any cache needs to be warmed up with the application working set before the application starts seeing the performance benefits. When the working set of the application changes, the cache automatically warms up with the new data over a period of time. 28 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

29 Chapter 3: Solution Overview XtremSW Cache in a virtualized environment The implementation of XtremSW Cache in a virtualized environment is slightly different from an implementation in a physical environment. In a virtualized environment, multiple virtual machines on the same server may share the performance advantages of a single XtremSW Cache card. VMware environment Figure 9 shows an XtremSW Cache implementation in a VMware virtualized environment. Figure 9. XtremSW Cache implementation in a VMware environment An XtremSW Cache implementation in a VMware environment consists of the following components: A physical XtremSF card on the VMware ESX Server. XtremSF firmware and driver on the ESX Server. XtremSW Cache software in each virtual machine that needs to be accelerated using XtremSW Cache. This includes the XtremSW Cache driver, command line interface (CLI) package, and XtremSW Cache Agent. Only virtual machines that need to be accelerated with XtremSW Cache must have XtremSW Cache software installed. The XtremSW VSI Plug-in for XtremSW Cache management in the VMware vcenter client. Both the raw device mapping (RDM) and Virtual Machine File System (VMFS) volumes are supported with XtremSW Cache. Network File System (NFS) file systems in VMware environments are supported as well. Figure 10 shows details of an implementation in a VMware environment. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 29

30 Chapter 3: Solution Overview Figure 10. XtremSW Cache in a VMware environment XtremSW Cache provides the flexibility to implement its caching capacity for one or many virtual machines in the ESX host from the VCenter server, with the VSI plug-in providing a single view for configuration and management: The XtremSF card installed on the ESX host should be configured as a datastore. Create a virtual disk (vdisk) in the XtremSW Cache datastore for the virtual machine as cache device. The size of the vdisk can be determined by the caching needs of the specific virtual machine. After the vdisk created on the XtremSW Cache datastore is added to the virtual machine, it can be used as the caching device just as in the physical environment. Any devices in the virtual machine that need XtremSW Cache acceleration can be configured to use this vdisk as the XtremSW Cache device for caching purposes. The caching on the same XtremSF card acts independently for each virtual machine. 30 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

31 Hyper-V environment Chapter 3: Solution Overview Figure 11 shows an implementation in a Hyper-V virtualized environment. Figure 11. XtremSW Cache in a Hyper-V environment An XtremSW Cache implementation in a Hyper-V environment consists of the following components: A physical XtremSF card on the Windows Hyper-V server XtremSF driver and firmware on the Windows Hyper-V server XtremSW Cache software on the Windows Hyper-V server In a Hyper-V environment, all the devices that need to be accelerated are configured at the Hyper-V root server level. The installation procedure is identical to the procedure for the physical Windows server. Unlike the VMware implementation, all virtual machines in the Hyper-V environment share the same physical XtremSF card installed on the Hyper-V server. Caching is provided through the Hyper-V host. In the Hyper-V environment, XtremSW Cache provides the caching capacity to support one or many virtual machines in the Hyper-V host: Virtual disks can be defined either before or after configuring the LUN as a source device. All virtual disks allocated on a source device LUN will be accelerated. NFS, Hyper-V virtual hard disk (VHDX), and physical pass-through disk types are all supported. Currently, cluster- shared volumes (CSV) are not supported. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 31

32 Chapter 3: Solution Overview 32 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

33 Chapter 4: Solution Design Considerations and Best Practices Chapter 4 Solution Design Considerations and Best Practices This chapter presents the following topics: Overview VSPEX environments that can benefit from XtremSW Cache XtremSF card selection Virtualization design considerations XtremSW Cache placement considerations VMware considerations Hyper-V considerations EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 33

34 Chapter 4: Solution Design Considerations and Best Practices Overview This chapter provides best practices and considerations for the XtremSW Cache implementation within the VSPEX Proven Infrastructure for various applications solution. We 1 considered the following aspects during the solution design: XtremSF card selection XtremSW Cache layout design Virtualization design VSPEX environments that can benefit from XtremSW Cache This section discusses the workload environments that can benefit from XtremSW Cache, as follows: Applications that have high read-to-write workload ratios: Maximum effectiveness is gained where the same chunks of data are read many times and seldom written. Applications with a small working set receive the maximum possible boost. Applications with predominantly random workloads: Sequential workloads tend to have a significantly larger, active dataset in proportion to the available XtremSW cache size (such as data warehousing), and so do not benefit greatly from XtremSW Cache. Applications with a high degree of I/O concurrency (that is, multiple I/O threads). Applications with smaller I/O sizes (8 KB or lower): However, applications that generate large I/O sizes, such as Exchange Server 2010, can still benefit. The XtremSW Cache software enables you to tune features such as page size and maximum I/O sizes, which greatly helps in these environments to continue to accelerate particular I/Os and avoid other I/Os (such as backup read I/Os). As explained in Chapter 3: Solution Overview, XtremSW Cache can accelerate read operations, while all write operations are written to the storage array and are not affected by XtremSW Cache. In many cases, improvement in write-throughput performance can be observed as XtremSW Cache offloads the read operations, enabling the array to handle more write operations as a side benefit. XtremSW Cache may not be suitable for more write-intensive or sequential applications such as data warehousing, streaming, media, or Big Data applications. Figure 12 shows these use cases. 1 In this guide, we refers to the EMC Solutions engineering team that validated the solution. 34 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

35 Chapter 4: Solution Design Considerations and Best Practices XtremSF card selection Figure 12. XtremSW Cache use cases The horizontal axis represents a typical read-to-write ratio for an application workload. The left side represents write-heavy applications such as backups. The right side represents read-heavy applications such as reporting tools. The vertical axis represents the working set of the application s workload. The lower end represents applications that have a very large working set and the top of the chart represents applications with a small working set, where the majority of the I/O goes to a very small set of data. Typically, applications with a small working set occupy less space in XtremSW Cache. The greatest performance improvement can be achieved with XtremSW Cache in highread applications with a highly concentrated, small working set of data. To summarize, you can use XtremSF as the local storage for read and write acceleration, temporary data, and large working sets, while XtremSF with XtremSW Cache can be used for read acceleration of mission-critical data with small working sets that require data protection. Overview In general, the two major technologies used in all Flash drives are: SLC NAND-based Flash cell Multilevel cell (MLC) NAND-based Flash cell This section discusses which card to select when designing an XtremSW Cache solution. EMC XtremSF has both SLC and MLC cards in different sizes to fit the different needs of a customer environment. For more information about XtremSF card sizes, see Table 3 Design best practices Flash storage devices store information in a collection of Flash cells made from floating gate transistors. SLC devices store only one bit of information in each Flash cell (binary). MLC devices store more than one bit per Flash cell by choosing between EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 35

36 Chapter 4: Solution Design Considerations and Best Practices multiple levels of electrical charge to apply to the floating gates in the transistors, as shown in Figure 13. Figure 13. Comparison between SLC and MLC Flash cell data storage Because each cell in MLC Flash has more information bits, an MLC Flash-based storage device offers increased storage density compared to an SLC Flash-based version. However, MLC NAND has lower performance and endurance because of its inherent architectural tradeoffs. Higher functionality further complicates the use of MLC NAND, which makes it necessary to implement more advanced Flash management algorithms and controllers. Table 4 compares the SLC and MLC Flash characteristics with some typical values. Table 4. SLC and MLC Flash comparison Features MLC SLC Bits per cell 2 1 Endurance (erase/write cycles) About 10,000 About 100,000 Read service time (Avg.) 129 μs 38 μs Write service time (Avg.) 1,375 μs 377 μs Block erase (Avg.) 4,500 μs 1,400 μs Although SLC NAND Flash offers a lower density, it also provides an enhanced level of performance in the form of faster reads and writes. Because SLC NAND Flash stores only one bit per cell, the need for error correction is reduced. SLC also allows for higher write and erase cycle endurance, making it a better fit for use in applications that require increased endurance and viability in multiyear product life cycles. SLC and MLC NAND offer capabilities that serve two different types of applications those requiring high performance at an attractive cost per bit (MLC), and those that are less cost sensitive and seeking even higher performance over time (SLC). 36 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

37 Virtualization design considerations Chapter 4: Solution Design Considerations and Best Practices Overview Sizing recommendations XtremSW Cache is fully supported when deployed in a virtual environment with VMware vsphere ESXi technology or Windows Server Hyper-V technology. The following describes the best practices and design considerations for XtremSW Cache in virtualized environments: Identify the virtual machines on the ESXi server that would be a good candidate for XtremSW Cache to accelerate its performance with reasonable cost. Calculate the total capacity needed for XtremSW Cache. If needed, adjust the placement of the virtual machines in the environment to best utilize XtremSW Cache. Select the appropriate XtremSF card for both capacity and performance. Sizing recommendations are available for each different application type. The implementation also varies for each different environment. The following are the minimum configurations recommended for each application, based on our testing in a controlled environment with a typical database workload and application workload. Use the numbers provided as a guideline. To determine the sizing that best fits a specific application and environment, it is important to consider both the performance level you need and the cost you can afford. In most cases, adding more XtremSW Cache gives better performance until the size of the cache is equal to or greater than the working set. Table 5 provides XtremSW Cache recommendations for each application. The cacheto-storage ratio (the cache and database storage size ratio, a 1:10 ratio, represents a 1 GB XtremSW Cache for each 10 GB of data) largely depends on the active working set of the database, and will change based on actual usage. Table 5. Recommended cache for each application Application Database type Read-to-write ratio SQL Server/ Oracle OLTP 90:10 1:10 SQL Server/ Oracle OLTP 70:30 1:5 SharePoint Server Content/crawl 100% read 1:5 Exchange Server Mailbox 60:40 1:100 Recommended XtremSW Cache-to-storage ratio 2 For Oracle or SQL Server online analytical processing (OLAP) applications, such as a data warehouse environment, emlc XtremSF (alone, or in split-card mode) can be used as the tempdb to improve the query performance. Consider at least 200 GB tempdb space for every 1 TB of database. 2 XtremSW Cache-to-storage ratio is the cache and database storage size ratio. If the ratio is 1:10, then for each 10 GB of data, provide at least 1 GB of XtremSW Cache. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 37

38 Chapter 4: Solution Design Considerations and Best Practices XtremSW Cache placement considerations Overview EMC XtremSW Cache can accelerate performance on demand for applications in a VSPEX Proven Infrastructure. The flexibility of an XtremSW Cache implementation enables you to place XtremSF on the server that hosts the specific virtual machines requiring performance acceleration. In those virtual machines, you enable only the specific storage LUNs that need XtremSW Cache. To ensure that those virtual machines continue to have access to XtremSW acceleration, set the appropriate affinity rules for the hypervisor so the virtual machines can reside only on those servers that are accelerated with XtremSF Cache. Additionally, you can install XtremSF Flash cards in all physical servers in the server infrastructure, and then install and enable XtremSW Cache across all servers. Design best practices Working from the base configuration of VSPEX, for each application you intend to run within the environment, determine which applications need XtremSW Cache acceleration. Next, consider the following for the best placement of the XtremSF card within the server infrastructure: Use XtremSF with XtremSW Cache for read acceleration of mission-critical data with small working sets that require data protection. Put at least two XtremSF cards within your VSPEX server infrastructure when redundancy is required. If vmotion is required, calculate the XtremSF capacity and placement so that the remaining server and XtremSF capacity still can serve the configured XtremSW Cache settings of all virtual machines when vmotion takes place. For example, if 10 virtual machines are configured to use 100 GB of XtremSW Cache, which requires a total of 1 TB of XtremSW Cache capacity, in the event of vmotion, the remaining servers in the virtualized cluster with XtremSW Cache need to facilitate at least 1 TB of cache space. If applications only need a small part of the XtremSF card capacity for each virtual machine, the virtual machines with these applications could share the same physical card and are best placed on the same ESXi or Hyper-V host. If a certain application demands all the available capacity of the XtremSF card, then the host should dedicate that specific card to the virtual machine. Multiple XtremSF cards can be installed on the same server, if required. Multiple XtremSF can be configured to the same hypervisor to create multiple cache devices for that virtual machine. For specific application workloads that have been selected to use the split-card feature, part of the card can be configured to serve the caching needs of the virtual machine; the other part can be configured as XtremSF storage to serve the need for a temporary datastore such as a tempdb storage space. 38 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

39 Chapter 4: Solution Design Considerations and Best Practices Additional considerations for the portability of the virtual machine in the virtualized environment are necessary for this configuration as the virtual machine now depends on the storage that is local to that server. XtremSW Cache configuration specifics: The XtremSW Cache page size is the smallest unit of allocation inside the cache. The default page size is 8 KB. The XtremSW Cache maximum I/O size is the maximum I/O size that will be promoted into the cache. The default maximum I/O size is set to 64 KB. Where possible, understand the I/O size distribution of all applications selected for acceleration. If an application generates significantly large I/O sizes (such as Exchange Server), this may warrant a change of the default page size and maximum I/O size configurations for XtremSW Cache. Refer to the relevant XtremSW Cache documents in the References section for information on how to correctly change these configuration settings. The minimum size for the XtremSW Cache vdisk is 20 GB for any virtual machine that needs Flash cache acceleration. There is minimal resource consumption (overhead) for virtual machines using XtremSW Cache to accelerate application performance, except when the deduplication feature is enabled. Resource consumption, including CPU and memory, depends on the application and especially depends on the size of the working set. Deduplication introduces very limited memory utilization and CPU consumption when enabled in an environment with a small working set and high skew. This is detailed in the Exchange solution example; for more information, see XtremSW Cache for Exchange Server. XtremSW Cache can be disabled or enabled any time once the XtremSF card is installed on the physical host and configured for the virtual machine. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 39

40 Chapter 4: Solution Design Considerations and Best Practices VMware considerations Overview Design best practices This section provides the most common and important design considerations for implementing XtremSW Cache in a VSPEX with VMware environment. The VMware environment in a VSPEX Proven Infrastructure should follow the general VSPEX design principles and best practices for specific applications on VMware, as detailed in the VSPEX Implementation Guides. XtremSF should be installed on each ESXi server with virtual machines that require XtremSW Cache acceleration, as determined by customer s performance and cost analysis. After the XtremSF Flash card is installed, it can be configured as the XtremSW Cache datastore on the ESXi server using the VSI plug-in, as shown in Figure 14. Figure 14. XtremSW Cache configuration using EMC VSI plug-in Although multiple XtremSW Cache devices for the same virtual machine are supported, one XtremSW Cache device for each virtual machine can sufficiently satisfy the caching needs for the majority of the use cases, as shown in Figure EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

41 Chapter 4: Solution Design Considerations and Best Practices Figure 15. XtremSW Cache implementation in VMware environment for VSPEX The size of the XtremSW Cache should follow the best practices for each different application, as previously described in the Sizing recommendations section. For multiple applications or database LUNs, simply add the required XtremSW Cache device size, and create a single XtremSW Cache device for the virtual machine, as shown in Figure 15. The only exception to this is when there is a need to segregate the I/O traffic, or when one XtremSF card is not big enough for the virtual machine, then multiple cards are needed. Since each virtual machine in the VMware environment has its own XtremSW Cache vdisk, there is no contention among different virtual machines for XtremSW Cache caching. Each deployment should be a careful balance of performance and cost considerations. As previously noted, virtual machines are expected to migrate across the VMware cluster. Ensure that sufficient XtremSW Caching capacity is available on other nodes to accept an incoming virtual machine configured for acceleration. For example, if you wish to move SQLVM1 (configured with a 50 GB cache) from host ESXServer1 to host ESXServer2 (through a vmotion migration), ensure that ESXServer2 has at least 50 GB of free XtremSW Cache capacity available. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 41

42 Chapter 4: Solution Design Considerations and Best Practices Hyper-V considerations Overview Design best practices This section provides the most common and important design considerations for implementing XtremSW Cache in a Hyper-V environment. The Hyper-V environment in a VSPEX implementation should follow the general VSPEX design best practices for the specific application in the Hyper-V environment, as detailed in the VSPEX Implementation Guides. As shown in Figure 16, install XtremSF on each Hyper-V server with virtual machines that require XtremSW Cache acceleration, as determined by the customer s performance and cost analysis. Once the XtremSF card is installed, configure it as the XtremSW Cache target device on the Hyper-V server. From the Hyper-V server, configure all the LUNs requiring XtremSW Cache acceleration as source LUNs for the XtremSW Cache target device. As shown in Figure 16, all VHDXs for the different virtual machines, as well as the physical pass-through disks on those LUNs configured as XtremSW Cache source LUNs, are accelerated by XtremSW Cache. Figure 16. XtremSW Cache implementation in Hyper-V environment for VSPEX Since XtremSW Cache in a Hyper-V environment works at the Hyper-V level, all the source devices from the different virtual machines are accelerated with the same XtremSW Cache target. This means: Applications may enjoy a higher level of service from XtremSW Cache when other virtual machines on the same Hyper-V server are not as active. This is because the source device is not limited to the calculated capacity of the XtremSW Cache and can potentially use all the available cache capacity. 42 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

43 Chapter 4: Solution Design Considerations and Best Practices There may be contention between different virtual machines if the workload and active data set (the hot data) on one of the virtual machines is overwhelmingly high and using more than its quota. To avoid contention, it is better to put applications that place a high demand on XtremSW Cache on different Hyper-V servers, or to configure them with a different XtremSF card on the same Hyper-V server. Currently, CSV volumes are not supported with XtremSW Cache 1.5x software. CSV volumes will be supported in future releases. Note: Volumes in a Hyper-V cluster do not need to be CSV to avail of the benefits of Live Migration or other advanced Hyper-V features. Also, in cases where Tier-1 applications require acceleration, it may be best not to enable CSV on those volumes and ensure they are dedicated to the application from the volume to LUN to storage array disks. When using VHDX, all VHDXs on the same LUN that are configured with XtremSW Cache are accelerated with XtremSW Cache. When designing the storage layout, consider placing only the VHDXs that require XtremSW Cache acceleration on the LUNs that are configured with XtremSW Cache. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 43

44 Chapter 4: Solution Design Considerations and Best Practices 44 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

45 Chapter 5: XtremSW Cache Solution for Applications Chapter 5 XtremSW Cache Solution for Applications This chapter presents the following topics: Overview Architecture of XtremSW Cache deployment on VMware Architecture of XtremSW Cache deployment on Hyper-V XtremSW Cache for SQL Server OLTP database XtremSW Cache for Exchange Server XtremSW Cache for SharePoint XtremSW Cache for Oracle OLTP database XtremSW Cache for private cloud EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 45

46 Chapter 5: XtremSW Cache Solution for Applications Overview Any VSPEX Proven Infrastructure that needs to boost the performance of applications such as Oracle and SQL Server OLTP applications, web applications, financial trading applications, and Exchange can benefit from XtremSW Cache. XtremSW Cache can be considered as an upgrade or add-on feature for a larger cloud solution. This section describes application use cases where XtremSW Cache provides value. It includes the best practices, the deployment scenarios, and the expected benefits for the following application use cases: SQL Server Exchange SharePoint Oracle Private cloud Architecture of XtremSW Cache deployment on VMware Figure 17 shows the validated architecture for an XtremSW Cache deployment on a VSPEX Private Cloud with VMware. The XtremSF card is installed on the physical VMware ESXi server and an XtremSW Cache datastore is created on it. The XtremSW Cache vdisk created in that datastore is assigned to the virtual machines hosting the application that needs to be accelerated. The vdisk can use part or all of the available storage in the XtremSW Cache datastore. On each virtual machine, the LUNs that will be accelerated by the XtremSW Cache are configured as source LUNs for the XtremSW Cache vdisk. After they are enabled, data is cached just as it is in a physical environment. The source LUN could be any LUN in the virtual machine, such as virtual machine data file for VMware (VMDK), RDM, and so on. 46 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

47 Chapter 5: XtremSW Cache Solution for Applications Figure 17. Architecture of the VSPEX Proven Infrastructure for XtremSW Cache deployment on VMware Architecture of XtremSW Cache deployment on Hyper-V Figure 18 shows the validated architecture for an XtremSW Cache deployment on a VSPEX Private Cloud with Hyper-V. In a Hyper-V environment, the XtremSW Cache is deployed on the Hyper-V host and managed from this level. The I/Os issued by the virtual machines are accelerated at the Hyper-V level. If there are multiple VHDXs on the same LUN in the Hyper-V host, they will all be accelerated because the XtremSW Cache source LUN is configured at the Hyper-V host level. If a VHDX is used in Hyper-V, the source LUN for XtremSW Cache on the Hyper-V host should contain only VHDXs that need to be accelerated. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 47

48 Chapter 5: XtremSW Cache Solution for Applications Figure 18. Architecture of the VSPEX Proven Infrastructure for XtremSW Cache deployment on Hyper-V XtremSW Cache for SQL Server OLTP database Overview In a SQL Server environment, the storage LUNs that host the database data files for the OLTP database are most likely to benefit from XtremSW Cache acceleration. The read-to-write ratio of a typical SQL Server OLTP database data file ranges from 70:30 to 90:10, making the database data file LUN ideal for XtremSW Cache acceleration. In the example use case described in this section, we tested an active OLTP database with a read-to-write ratio of 90:10. Using about a 100 GB cache to accelerate a 1 TB OLTP database reduced the read latency by more than half. 48 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

49 Chapter 5: XtremSW Cache Solution for Applications Benefits of XtremSW Cache in a SQL Server OLTP environment Best practices XtremSW Cache is proven to be highly scalable and reliable. It can relieve the I/O processing pressure from the storage system and boost the disk read operations driven by the host, even in virtual ESXi-based environments. XtremSW Cache increases the overall transaction rate of SQL Server and significantly reduces disk latencies with minimal impact on system resources. XtremSW Cache in SQL Server OLTP environments provides the following benefits: XtremSW Cache can reduce SQL Server storage response time. The XtremSW Cache host driver has minimal impact on server and virtual machine system resources. In testing, the system resources were mostly consumed by the SQL Server workload. The XtremSW Cache driver overhead was negligible 0.4 percent CPU usage in this example use case. With a highly optimized, multitier storage system, XtremSW Cache can offload read I/O processing from the storage array while reducing disk latencies, thus enabling higher transactional throughput and enabling the EMC storage array to consume even more workload. With less optimized, two-tier storage configurations, XtremSW Cache can significantly boost SQL Server transactions and lower overall host disk latency. It can address hot-spots in the datacenter and alleviate possible storage bottlenecks. We observed a performance boost immediately after the LUNs were added to the XtremSW Cache pool. Performance reached a steady state in approximately one hour for all 16 LUNs hosting a 3 TB database file. XtremSW Cache is a server-based cache. Introducing XtremSW Cache to a storage environment does not require any changes to the application or storage system layouts. Because XtremSW Cache is a caching solution rather than a storage solution, there is no need to move data. Therefore, you do not risk having inaccessible data if the server or the PCIe card fails. XtremSW Cache minimizes CPU overhead in the server by offloading Flash management operations from the host CPU onto the PCIe card. Managing and monitoring XtremSW Cache in a vsphere environment is easy. After configuration, XtremSW Cache requires no user intervention and continuously adjusts to meet the needs of the application workload. In a SQL Server OLTP environment running a heavy OLTP workload, the primary database LUNs can benefit most from XtremSW Cache acceleration. The log LUNs and tempdb LUNs are write-heavy and should not be used with the XtremSW Cache. In summary, in a typical SQL Server OLTP environment: The read-intensive database data file LUNs generally have heavy workload, subjected to a high-read skew, and are good candidates for XtremSW Cache. SQL Server OLTP data files experience constant random reads and contribute to the overall duration of transaction times. Data files also experience regular bursts of write activity during a checkpoint operation. Using XtremSW Cache to EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 49

50 Chapter 5: XtremSW Cache Solution for Applications cache reads and avoid an I/O workload on the EMC array enables the array to consume those burst writes faster and avoid any read delays for transactions. Log LUNs and tempdb LUNs in OLTP databases are write-intensive and typically do not benefit from XtremSW Cache. In SQL Server AlwaysOn environments, the secondary databases do not need to be accelerated unless a specific performance requirement justifies the use of XtremSW cache. Set the page size to 64 KB in the XtremSW Cache to accommodate the large I/O for the SQL Server database. If the workload is not expected to increase after deploying XtremSW Cache in the VSPEX Proven Infrastructure, there is no need for additional system resources such as memory or CPU. With a read-to-write ratio of 90:10 in the OLTP database LUNs, for each 1 TB of database, an XtremSW Cache of 100 GB or more would significantly improve the OLTP query performance and read operations. Use case design and deployment The example use case deployed XtremSW Cache to accelerate OLTP performance in a multiuser SQL Server 2012 database virtualized with the VMware environment. Two ESXi servers each hosted one SQL Server virtual machine. One of the SQL Server virtual machines used a 700 GB SLC XtremSF card. The other server did not have XtremSW Cache configured. The environment is based on a multitier storage solution that is controlled and optimized by EMC Fully Automated Storage Tiering for Virtual Pools (FAST VP). The solution design includes the following components and features as shown in Figure 19: Two vsphere ESXi servers, each hosting one SQL Server virtual machine XtremSW Cache enabled on the primary SQL Server virtual machine 50 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

51 Chapter 5: XtremSW Cache Solution for Applications Figure 19. Architecture design for XtremSW Cache enabled SQL Server virtual environment Deployment scenarios Figure 20 shows the XtremSW Cache deployment for this use case. All the database file LUNs on the primary server are configured as source LUNs for XtremSW Cache acceleration; tempdb LUNs and log LUNs are excluded. The secondary server does not have XtremSW Cache configured. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 51

52 Chapter 5: XtremSW Cache Solution for Applications Figure 20. SQL Server AlwaysOn XtremSW Cache deployment Configuration of XtremSW Cache in the VMware environment In this solution, we configured one 278 GB XtremSW Cache. All 16 source data devices were associated with the cache device, as shown in Figure 20. Configuration is straightforward using the wizards in the VSI integrated plug-in. If preferred, you can use the command line from the Windows virtual machine. We used the following steps to configure the XtremSW Cache for the database LUNs in the virtual machine: 1. Use vcenter Server to create a VMFS datastore on the cache device. 2. Add the XtremSW Cache device in the form of virtual disks to the virtual machines through the VSI plug-in for XtremSW Cache. You can add the entire device to one virtual machine or partition it into virtual disks that can be used for different virtual machines. The XtremSW Cache virtual disk is shown in the Disk Management wizard of the virtual machine as an Original Equipment Manufacturer (OEM) partition. 3. Add the source devices to the enabled XtremSW Cache device to accelerate their performance. Any source device can be stopped temporarily or removed from the caching operation without affecting other source devices. Test results XtremSW Cache boosts system performance After enabling XtremSW Cache for the first time, the performance boost was visible immediately. XtremSW Cache started to take effect as soon as it was enabled with the devices needing a performance boost added into the cache pool. It took approximately one hour in this environment to reach the maximum performance boost. We tested XtremSW Cache for SQL Server in both a two-tier and a three-tier configurations. Figure 21 shows the read and write IOPS for the primary SQL Server before and after enabling XtremSW Cache in a two-tier storage system. 52 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

53 Chapter 5: XtremSW Cache Solution for Applications 20, ,000 10,000 5, latency (ms) IOPS IOPS and latency change after enabling XtremSW Cache Baseline XtremSW Cache Steady state 0 0 IOPS latency ( ms) Figure 21. Performance boost after enabling XtremSW Cache After the system reached the steady state, the system performance was stable during the 24-hour testing period. XtremSW Cache reduces SQL Server response time XtremSW Cache significantly reduced the SQL Server response time for high response time transactions in both the two-tier and three-tier configurations. The XtremSW Cache host driver had a minimal impact on the server and virtual machine system resources. The read latency reduced by approximately 50 to 70 percent after we enabled XtremSW Cache. We observed a similar result with the transaction latency, where XtremSW Cache also significantly lowered the response time of high latency transactions. Without XtremSW Cache, the two-tier configuration can support only 14,000 IOPS. With XtremSW Cache, it can fully support a 24,000 IOPS load with a 90:10 read-towrite ratio. XtremSW Cache significantly lowered the I/O activities on the storage array (about 10,000 IOPS) in the three-tier configuration, thus enabling the storage system to support more server I/O requests. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 53

54 Chapter 5: XtremSW Cache Solution for Applications Table 6 shows the detailed test results for all the test scenarios in this solution. Table 6. Performance data with OLTP load Three-tier storage Two-tier storage Performance Without XtremSW Cache With XtremSW Cache Without XtremSW Cache With XtremSW Cache SQL Server virtual machine CPU 67.45% 67.85% 15.50%* 51.43% ESXi CPU 77.80% 78.20% 24.63%* 65.57% Client transactions per second (TPS) 2,193 2,585 1,225 2,229 SQL Server virtual machine IOPS 23,938 23,916 14,123 23,602 Array front-end IOPS 24,698 14,987 15,475 13,798 Latency (ms) (read/write/transfer) 4/1/4 2/2/2 11/1/10 4/3/4 * CPU usage was lower because the storage bottleneck created in this test limited the client load that can be pushed to the system. XtremSW Cache for Exchange Server Overview In an Exchange Server environment, the Exchange database LUNs are most likely to benefit from XtremSW Cache acceleration. The performance of the database can be improved by using 10 GB of XtremSW Cache for each 1 TB of Exchange data in the Mailbox server virtual machines in the example use case described in this section. Even though the typical Exchange Mailbox workload has about a 60:40 read-to-write ratio and a large I/O size, the working set of the Exchange databases is very small. This means that the Mailbox workload performance can be dramatically improved when a small slice of XtremSF is configured as XtremSW Cache for the Mailbox database LUNs. The high I/O skew in this use case also makes it a good candidate for deduplication with limited memory and CPU consumption. Benefits of XtremSW Cache in an Exchange environment Using XtremSW Cache in an Exchange environment offers many benefits: XtremSW Cache improves Exchange performance by reducing read latencies and offloading read operations from the back-end storage. XtremSW Cache helps to maximize I/O throughput for Exchange workloads without changing or adding any additional storage resources. XtremSW Cache reduces bandwidth requirements through deduplication features, offloading write processing from the Exchange back-end storage. 54 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

55 Chapter 5: XtremSW Cache Solution for Applications XtremSW Cache can be integrated with vsphere for virtual machine migration that has an XtremSW Cache device attached. With proper configuration, the applications can resume the accelerated state after virtual machine automigration occurred. XtremSW Cache has little impact on system resources such as CPU and memory. The initial warm-up period for XtremSW Cache with Exchange-simulated workloads varies for each environment. In this solution, the effect of XtremSW Cache was observed immediately after it was enabled. It reached a steady state in approximately 30 minutes for all Exchange accelerated database LUNs with 15 TB of data. Integration with the VSI plug-in for VMware makes XtremSW Cache easy to manage and monitor in a virtualized environment. XtremSW Cache is designed to minimize CPU overhead in the server by offloading Flash management operations from the host CPU onto the XtremSF PCIe card. With an Exchange workload, XtremSW Cache can relieve I/O processing pressure from the storage system and boost the disk read operations driven by the host. XtremSW Cache increases the overall Exchange application IOPS and significantly reduces disk latencies with minimal impact on system resources. Using XtremSW Cache enables customers to configure Exchange for high performance and low cost without making trade-offs. Managing and monitoring XtremSW Cache in a vsphere environment is easy. After configuration, XtremSW Cache requires no user intervention and continuously changes to meet the application workload requirements. Best practices In Exchange with a Database Availability Group (DAG) environment (for both active and passive copies of DAG), the LUNs for the databases can benefit most from XtremSW Cache acceleration. More importantly, the working set for Exchange database is relatively small; thus, the XtremSW Cache size needed for Exchange server acceleration is also small. In this use case, every 1 TB of Exchange data requires only about 10 GB of XtremSW Cache. Enabling XtremSW Cache acceleration for both active and passive databases also improves the performance. If there is a DAG failover, XtremSW Cache is already warm when the DAG fails over and the whole Exchange environment shows almost no performance impact. The LUNs for the database log should be excluded because of their sequential workload. In summary, in a typical Exchange environment: In Mailbox virtual machines, typically both active and passive database file LUNs with a heavy workload are good candidates for XtremSW Cache source LUNs. XtremSW Cache also helps improve the performance even in a DAG failover scenario. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 55

56 Chapter 5: XtremSW Cache Solution for Applications Typically, log LUNs are excluded from XtremSW Cache. Set the page size to 64 KB in XtremSW Cache to accommodate the large I/O size of the Exchange Server. For each Exchange virtual machine, for every 1 TB of Exchange data, configuring about a 10 GB XtremSW Cache can significantly improve the Mailbox server performance. Use case design and deployment The example use case deployed XtremSW Cache to accelerate the performance of Exchange 2010 in a DAG configuration with two database copies virtualized with the VMware environment. We installed two 700 GB SLC XtremSF cards on the vsphere ESXi servers hosting six Exchange Mailbox server virtual machines. In testing, the system IOPS improved by over 26 percent, and read latencies decreased by about 50 to 70 percent. We also tested the environment for deduplication with little additional system resource consumption. When enabling XtremSW Cache deduplication for Exchange Server, you can reduce the CPU usage by up to 50 percent in certain workloads, with a drop of up to 30 percent in the write IOPS to the back-end array. Figure 22 shows the solution design, which included the following components: A vsphere HA cluster consisting of two vsphere ESXi servers, each hosting three Exchange Mailbox server virtual machines Two copies of the DAG database configured on different Mailbox servers XtremSF installed on both EXSi servers in the HA cluster Each Exchange Mailbox server virtual machine configured with a 50 GB XtremSW Cache for their 5 TB databases (including both active and passive DAG copies). 56 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

57 Chapter 5: XtremSW Cache Solution for Applications Figure 22. Architecture design for XtremSW Cache-enabled Exchange virtual environment Deployment scenarios Figure 23 shows the XtremSW Cache deployment for the Exchange use case. We configured all database LUNs for active and passive copies on the virtual machines as source LUNs for XtremSW Cache acceleration. The log LUNs were excluded mostly because of their write and sequential I/O. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 57

58 Chapter 5: XtremSW Cache Solution for Applications Figure 23. XtremSW Cache deployment for Exchange 2010 on vsphere In this deployment, for each virtual machine with 5 TB of storage, we deployed 50 GB of XtremSW Cache. We configured the rest of the XtremSW Cache capacity to support the vmotion failover. Configuration of XtremSW Cache in the VMware environment The configuration of XtremSW Cache for an Exchange Mailbox server in a VMware environment is similar to the SQL Server configuration previously shown in Figure 20. In addition, for this use case, we configured deduplication and vmotion migration. You can configure the XtremSW Cache data deduplication feature for the Exchange Mailbox server virtual machines. Data deduplication eliminates redundant data by storing only a single copy of identical chunks of data while, at the same time, providing access to the data from the cache. Deduplication also helps to reduce storage and bandwidth requirements and extend the life expectancy of the cache device. Configuring the XtremSW Cache device with data deduplication To enable data deduplication for the XtremSW Cache device, follow these steps: 1. Select the Use Data Deduplication checkbox in the Add XtremSW Cache Device wizard, when adding the XtremSW Cache device to a virtual machine. 58 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

59 Chapter 5: XtremSW Cache Solution for Applications 2. Select the expected data deduplication percentage gain based on your Exchange workload type, as shown in Figure 24. Figure 24. Enabling data deduplication on the XtremSW Cache device You can also enable data deduplication using the XtremSW Cache CLI on the Windows client machine by running the following command: vfcmt add -cache_dev harddisk13 set_page_size 64 set_max_io_size 64 enable_ddup ddup_gain 20 Where: harddisk13 ddup_gain 20 Is: A configured operating-system cache device for the virtual machine The deduplication gain percentage for the system cache device on the virtual machine After adding the deduplication-enabled XtremSW Cache device, add the Exchange database LUNs as source devices to the XtremSW Cache device for performance acceleration. To determine the appropriate data deduplication gain for your Exchange workload, review the XtremSW Cache statistics information in the XtremSW Cache VSI plug-in or use the CLI on the Windows server. After the cache warm-up, follow these recommendations: Calculate the observed deduplication hit ratio and compare it with the configured ratio. Calculate the observed deduplication hit ratio by dividing the Write Hits by the Writes Received. This is the amount of duplicated data in the cache. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 59

60 Chapter 5: XtremSW Cache Solution for Applications If the observed ratio is less than 10 percent, turn off deduplication or reconfigure the deduplication gain to zero percent. To benefit from the extended life of the cache device, keep deduplication enabled. If the observed ratio is over 35 percent, raise the deduplication gain to match the observed deduplication. If the observed ratio is between 10 and 35 percent, leave the deduplication gain as it is. To change the configured ratio, remove the XtremSW Cache device from the Exchange Mailbox server virtual machine, and add it back again with a new deduplication percentage value. To do this, use the VSI plug-in or the CLI command (vfcmt add - cache_dev), as described previously in this section. Migrating an Exchange virtual machine with XtremSW Cache device It is possible to move an Exchange virtual machine that has an XtremSW Cache disk from one vsphere host to another. Under a typical scenario, without an XtremSW Cache device, you can use the native vsphere migrate command to move a virtual machine from one host to another. This is possible because in a typical scenario the virtual machine s datastores and RDMs are shared resources. In the XtremSW Cache environment, however, the XtremSW Cache datastore is mapped to its local host Flash drive. Consequently, this datastore is accessible only to that host and the native vsphere migrate command is not supported. Instead, use the EMC XtremSW Cache VSI plug-in to perform the virtual machine migration with the XtremSW Cache device attached. Multiple forms of migration are available. The form of migration that you choose determines the steps you perform to complete the migration. Before you begin, ensure that your system meets the following prerequisites: The target datastore has enough available capacity for the new device. There are no additional DAS Flash-based devices for the host virtual machine. Only one XtremSW Cache device is configured on the host virtual machine. The virtual machine you want to migrate is not currently being migrated. The source host and the target host must be able to communicate with each other, so ensure the IP and Domain Name System (DNS) have been properly configured. Performing an automated migration An automated migration does not require disrupting the virtual machine; however, the cache will be cleared, thus resulting in a cold cache start. A warning message is displayed during the migration indicating that a cold cache start will occur after the migration. 60 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

61 To perform the migration, complete the following steps: Chapter 5: XtremSW Cache Solution for Applications 1. From the XtremSW Cache window of a virtual machine, click Migrate Virtual Machine. 2. Select the target host and target datastore. Only hosts within your datastores that are available to the host XtremSW Cache device are listed. 3. Click OK. A warning message is displayed stating that a cold cache start will take place after the migration, as shown in Figure 25. Figure 25. Cold cache start post migration warning 4. Click Yes to start the migration. Follow the task s progress in the Task window. Figure 26 shows details of the virtual machine migration wizard. Figure 26. EMC XtremSW Cache VSI-plug-in for virtual machine migration wizard EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 61

62 Chapter 5: XtremSW Cache Solution for Applications After a successful migration, a confirmation message appears in the message pane in the VSI management window. Recovering Exchange data from a snapshot If you are using backup software that performs snapshots of Exchange LUNs accelerated by XtremSW Cache, follow specific procedures when restoring data from those snapshots to ensure data integrity. If an Exchange LUN snapshot is taken on the array, and later used to roll back changes on the source LUN, the server will not be updated with the changes. This could result in the cache supplying data that may not been updated with the contents of the snapshot. To prevent this from occurring, when recovering from the snapshot, perform the following steps: 1. Quiesce the application that is accessing the source volume using application-specific tools, such as EMC Replication Manager. 2. Flush the data in the host buffers using an appropriate command, such as admsnap flush, and unmount the file system. 3. Invalidate the contents of the source device by using the purge - source_dev command. 4. Perform the snapshot restore operations on the array. 5. After the restore is complete, remount the file system, as necessary. Test results XtremSW Cache acceleration test results We observed consistent reductions in read latencies and increased user IOPS with all workload types when we enabled XtremSW Cache to accelerate performance for the database LUNs. Even 300-message workloads that experienced over 20 ms read latencies without XtremSW Cache became a normal steady workload with reduced latencies and increased IOPS with XtremSW Cache enabled. This extreme workload was expected to fail as the storage and Exchange virtual machine resources were originally designed for 150-message workloads. Figure 27 provides additional details for each test performed. Highlights of the observed test results include: A 150-message per user per day workload achieved a 51 percent reduction in read latencies (by 6.4 ms) and a 14.6 percent increase in user IOPS (by 224 IOPS). A 250-message per user per day workload achieved a 69.3 percent reduction in read latencies (by 11.1 ms) and a 12.8 percent increase in user IOPS (by 275 IOPS). A 300-message per user per day workload achieved a 56.8 percent reduction in read latencies (by 12.5 ms) and a 12 percent increase in user IOPS (by 346 IOPS). 62 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

63 Chapter 5: XtremSW Cache Solution for Applications Figure 27. Exchange 2010 performance with XtremSW Cache and LoadGen workload Performance with XtremSW Cache data deduplication To validate Exchange performance with XtremSW Cache inline data deduplication, we performed validation on one Exchange virtual machine with 5,000 users. We performed a series of Microsoft Exchange Load Generator (LoadGen) tests, with each test lasting eight hours and with multiple workload profiles, to see the effect of data deduplication. We monitored the XtremSW Cache statistics to determine the appropriate deduplication ratio for each workload. With the LoadGen workloads we generated, we observed that a 30 percent deduplication ratio would be more effective than the default 20 percent. Figure 28 shows the deduplication ratio observed during testing. Figure 28. XtremSW Cache statistics with data deduplication Note: The LoadGen workload does not represent the actual workload in your specific production environment. The results observed and recommendations provided here are based on our lab configuration and results only. Ensure that you configure your environment based on your particular workload requirements and characteristics. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 63

64 Chapter 5: XtremSW Cache Solution for Applications Deduplication test results summary In Figure 29 and Figure 30, the XtremSW Cache data deduplication test results with multiple workload profiles for the Exchange 2010 Mailbox server show: Decreased Exchange Server CPU utilization with each workload Slightly increased write latencies due to XtremSW Cache analysis and processing of the duplicated data Figure 29. Exchange server CPU utilization with XtremSW Cache data deduplication Figure 30. Exchange server disk latencies with XtremSW Cache data deduplication Analysis of the back-end VNX storage array shows that when we enabled deduplication on the server, the writes to the VNX array were reduced. In Figure 31, 64 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

65 Chapter 5: XtremSW Cache Solution for Applications the write activity was reduced from 90 IOPS to around 65 IOPS for one of the database LUNs, which is about a 27.7 percent difference. Figure 31. Exchange database LUN performance with XtremSW Cache data deduplication XtremSW Cache for SharePoint Overview Benefits of XtremSW Cache in a SharePoint environment Best practices For the SharePoint environment, content database and crawl database LUNs are most suitable for XtremSW Cache acceleration. A typical SharePoint content database workload has a 70:30 read-to-write ratio, making it an ideal candidate for XtremSW Cache acceleration. With two 600 GB XtremSW Cache devices configured on two 700 GB XtremSF cards, the database latency can drop to less than one third during a full crawl. This use case demonstrates the following results: XtremSW Cache offloads the read workload of the SharePoint content database workload during the crawl process from the storage array to the server. XtremSW Cache improves the crawl performance by lowering the latencies in the content database of the SharePoint farm in a virtualized environment. XtremSW Cache has little impact on system resources such as CPU and memory. Integration with the VSI plug-in for VMware vsphere vcenter makes XtremSW Cache easy to manage and monitor in a virtualized environment. In a SharePoint environment, the LUNs for the content databases during the crawl process can benefit most from XtremSW Cache acceleration. Thus the database file LUNs for the content database should be good candidates for the XtremSW Cache source LUNs. Exclude the log LUNs and tempdb LUNs from the XtremSW Cache as they are mostly write-heavy. In summary, in a typical SharePoint Farm: The content database file LUNs and crawl database LUNs with a heavy workload are good candidates for the XtremSW Cache source LUNs. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 65

66 Chapter 5: XtremSW Cache Solution for Applications Log LUNs and tempdb LUNs in the SharePoint farm are excluded from the acceleration of XtremSW Cache. Set the page size to 64 KB and the maximum I/O size to 128 KB in the XtremSW Cache to accommodate the large I/O size of the content and crawl databases, especially when NFS is in use. For each 1 TB of the content database, an XtremSW Cache of 200 GB or more can significantly improve the OLTP query performance. Use case design and deployment The example use case deployed a virtualized SharePoint 2010 farm with 1.8 TB content databases in one SQL Server 2012 virtual machine in a vsphere 5.1 virtualized environment, configured with two 700 GB XtremSF cards. You can improve the performance of the SharePoint crawl by: Deploying 600 GB XtremSW Cache in the SQL Server virtual machine Configuring all the content database file LUNs and the crawl database file LUNs to be accelerated by the XtremSW Cache The latency for these LUNs decreases dramatically and the crawl performance improves by more than 20 percent. The configuration of XtremSW Cache for SharePoint in a VMware environment is similar to the SQL Server configuration. Only the SQL Server virtual machine in the SharePoint farm needs XtremSW Cache acceleration. The solution design includes the following components, as shown in Figure 32: XtremSF installed on vsphere ESXi servers hosting the SQL Server virtual machine for SharePoint Server XtremSW Cache enabled on the SQL Server virtual machine, only configured for the content databases and the crawl databases Storage tiers with FAST VP enabled 66 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

67 Chapter 5: XtremSW Cache Solution for Applications Figure 32. Architecture design for XtremSW Cache enabled SharePoint environment Deployment scenarios Figure 33 shows the XtremSW Cache deployment for this use case. All the content database file LUNs are configured as source LUNs for XtremSW Cache acceleration, but tempdb LUNs and log LUNs are excluded. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 67

68 Chapter 5: XtremSW Cache Solution for Applications Figure 33. XtremSW Cache deployment for SharePoint 2010 on vsphere Configuration of XtremSW Cache in the VMware environment In this solution, two cache devices with a usable size of 600 GB out of the 700 GB XtremSW Cache card are configured for the content database virtual machine. All the LUNs for the content databases data file and the crawl database data file are associated with the two cache devices. During the crawl process, the content database data file is 100 percent random read and the crawl database data file is around 60 percent read. Set the I/O page size for the cache device to 64 KB (the default is 8 KB) and the maximum I/O size to 128 KB (the default is 64 KB). Test results The Read Hit rate for the content database during a full crawl is about 70 to 75 percent, and the crawl database is around 40 percent. The hard disks that store the content databases all have an over 70 percent Read Hit rate. The Read Hit rate is around 40 percent for the crawl database hard disk. The latency of the content databases and crawl database dropped dramatically after we enabled the cache device, as shown in Figure 34. Note that the property database is not configured as source devices for cache. The latency drop contributed to the property database improvement because it was in the same disk pool in the storage 68 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

69 Chapter 5: XtremSW Cache Solution for Applications array. As the I/Os on the backend for the content and crawl database were offloaded to the XtremSW Cache, a side effect was an improvement in the latency for the property database. Figure 34. Content database latency dropped after enabling XtremSW Cache The full crawl duration decreased by 21.2 percent when XtremSW Cache was enabled, as shown in Figure 35. Figure 35. Full crawl performance improved after enabling XtremSW cache EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 69

70 Chapter 5: XtremSW Cache Solution for Applications XtremSW Cache for Oracle OLTP database Overview In the VSPEX for virtualized Oracle environment, the database LUN for the OLTP database is most likely to benefit from XtremSW Cache acceleration. We tested a database with a read-to-write ratio of 70:30. Within an XtremSW Cache of 200 GB to accelerate 1 TB of the database LUN, the transaction rate almost doubled. Benefits of XtremSW Cache in an Oracle environment Best practices Similar to the application environments described previously, the VSPEX for virtualized Oracle environment will benefit from XtremSW Cache as a server-based cache. Introducing the XtremSW Cache virtual infrastructure does not require any changes to the application or storage system layouts. Because XtremSW Cache is a caching solution rather than a storage solution, there is no need to move data. Therefore, your data is not at risk of becoming inaccessible if the server or the PCIe card fails. XtremSW Cache is designed to minimize CPU overhead in the server by offloading Flash management operations from the host CPU to the PCIe card. In an virtualized Oracle OLTP environment, XtremSW Cache: Delivers an 80 percent improvement in transactions per minute (TPM) compared to the baseline without any changes to applications Maintains the integrity of and protects the data In an Oracle Database 11g R2 environment, the database file LUNs can benefit most from XtremSW Cache acceleration and are good candidates for the XtremSW Cache source LUNs. In summary, in a typical Oracle OLTP environment: The database file LUNs with a heavy workload are good candidates for the XtremSW Cache source LUNs. Log LUNs and tempdb LUNs in the OLTP databases are excluded from the acceleration of XtremSW Cache. For each 1 TB of database with a read-to-write ratio of 70:30, an XtremSW Cache of 200 GB or more can significantly improve the performance of the database. Use case design and deployment The example use case deployed a standard TPC-C-like OLTP workload, with a 1.2 TB database and a 70 to 30 percent read/write mix on Oracle Database 11g R2 on a Red Hat Enterprise Linux 5 virtual machine virtualized with vsphere 5.1. By deploying 250 GB of usable XtremSW Cache in the Oracle virtual machine from a single 350 GB XtremSF card, the performance of the workload can be dramatically improved. The transactions per minute improved 80 percent compared with the same environment without XtremSW Cache. The solution design includes the physical components shown in Figure 36: A single vsphere ESXi server hosting one Oracle Database 11g R2 server on a Red Hat Enterprise Linux 5 virtual machine 70 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

71 Chapter 5: XtremSW Cache Solution for Applications A 1.2 TB database on eight VMDK LUNs for the database files and two VMDK LUNs for the logs XtremSF installed on the EXSi server with a 250 GB XtremSW Cache configured for the Oracle virtual machine We configured only database VMDKs as source LUNs for XtremSW Cache. We excluded the log LUNs and the tempdb LUNs. Figure 36. Architecture design for XtremSW Cache enabled Oracle 11g R2 environment Deployment scenarios Figure 37 shows the XtremSW Cache deployment for the Oracle use case. We configured all the database VMDK LUNs on the virtual machines as source LUNs for XtremSW Cache acceleration. We excluded log LUNs because of their write-intensive nature. In this deployment, we configured 250 GB of XtremSW Cache for caching 1.2 TB of the OLTP database. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 71

72 Chapter 5: XtremSW Cache Solution for Applications Figure 37. XtremSW Cache deployment for Oracle 11g R2 on vsphere Configuration of XtremSW Cache in a VMware environment Test results The configuration of XtremSW Cache for Oracle in a VMware environment is similar to the configuration of the other application environments described in the previous sections. Figure 38 compares the overall system throughput (in TPM) of the baseline and XtremSW Cache-enabled environments. The availability of the hot data in the server s XtremSW Cache resulted in an 80 percent improvement in transactions per minute. Figure 38. OLTP TPM improvement 72 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

73 Chapter 5: XtremSW Cache Solution for Applications XtremSW Cache for private cloud Overview This use case deployed the XtremSW Cache to accelerate performance of the following applications in a private cloud environment virtualized with VMware: Oracle Database 11g R2 OLTP database SQL Server OLTP database SQL Server decision support system (DSS) database SQL Server 2012 cluster In the Oracle and SQL Server OLTP virtual machines, we configured the XtremSW Cache based on the principals described in the previous application-specific sections. The cluster support configured XtremSW Cache for both active and passive databases. SQL Server DSS uses XtremSF storage in a split configuration for the tempdb of the DSS database. With a comprehensive private cloud environment, XtremSW Cache and XtremSF proved to be flexible and were able to deliver the expected performance improvement for all the applications in different configurations. XtremSW Cache is proven to complement FAST VP for performance improvement of both the SQL Server and Oracle OLTP databases. The tempdb, supported by XtremSF in the database for the DSS workload, gets a performance boost from the XtremSF. Benefits of XtremSW Cache in a private cloud environment This EMC solution has shown the implementation of multiple critical applications in a VMware private cloud environment, supported by XtremSF and XtremSW Cache. Each application had different workload characteristics and placed varying demands on the underlying storage. XtremSW Cache provided better performance for the applications that involve heavy read I/O. The benefits of XtremSW Cache in a private cloud environment include the following: Performance optimization accelerating application-specific performance at the host level using EMC XtremSF cards: With a three-tier FAST VP configuration, XtremSW Cache offloads the IOPS of the array significantly. The array can be free for other I/O requests. With a two-tier FAST VP configuration, XtremSW Cache reduces disk latencies and response times, enabling a higher transaction throughput. XtremSW Cache reduces disk latencies and response time, enabling higher transaction throughput by offloading much of the read I/O traffic from the storage array. XtremSW Cache caches the read I/O so the data is not at risk of being inaccessible if the server or the XtremSW Cache card fails. Using XtremSF storage in a split-card configuration for the tempdb of the DSS database boosts the performance of the tempdb. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 73

74 Chapter 5: XtremSW Cache Solution for Applications XtremSW Cache in a virtualized environment is easy to manage and monitor due to its integration with the VSI plug-in to VMware vsphere vcenter. XtremSW Cache deduplication helps to reduce the footprint on bandwidth. In this private cloud environment, XtremSW Cache demonstrated both flexibility and ease of management in a comprehensive configuration, improving performance while having little impact on system resource consumption. Best practices Use case design and deployment In a private cloud environment, multiple applications need to be considered. Follow the application-specific best practices, particularly for the deployment of XtremSW Cache in a heterogenic environment: Allocate XtremSW Cache for the most critical application virtual machine first, and then consider the rest of the virtual machines. Consider placing virtual machines on a different physical server to optimize the capacity of XtremSF. MLC XtremSF (alone or in split-card mode) can be used as a tempdb for data warehouse or DSS types of databases. To improve query performance, consider allowing at least 200 GB of tempdb space for every 1 TB of database. In the example use case, Microsoft SQL Server 2012 (two OLTP and one DSS), Oracle Database 11g R2 (OLTP), and Microsoft SQL Server failover clustering are all on the virtualized environment. These applications ran on virtual machines in a VMware vsphere 5 environment on FAST VP-enabled EMC storage, which continually monitors and tunes performance by relocating data across tiers based on access patterns and predefined FAST policies. We deployed XtremSF on both ESXi servers, one configured in a split-card mode. We configured XtremSW Cache to support the OLTP databases for caching purposes, while using the remaining XtremSF capacity for the storage of tempdb in the DSS database. Load generation tools drove these applications simultaneously to validate the infrastructure and function of XtremSW Cache acceleration to the data LUNs of the OLTP application. The solution design included the following components, as shown in Figure 39: Two vsphere ESXi servers, one hosting the Oracle Database 11g R2 server and a SQL Server virtual machine as part of Microsoft Server failover cluster; the other hosting the other SQL Server of the MSCS, two SQL Servers with OLTP, and one SQL Server with a DSS workload. XtremSF configured in split-mode is used as tempdb storage for the SQL Server virtual machine with the DSS workload. XtremSW Cache enabled on all other virtual machines. FAST VP-enabled storage tiers. 74 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

75 Chapter 5: XtremSW Cache Solution for Applications Figure 39. Architecture design for XtremSW Cache-enabled private cloud environment with multiple applications Deployment scenarios Table 7 shows the XtremSW Cache deployment for the private cloud use case. The configuration of the database LUNs follows the same best practices as the application-specific use cases, such as source LUNs for XtremSW Cache acceleration. We excluded the log LUNs because they have mostly write and sequential I/O. We used XtremSF in split mode for the DSS tempdb store to accelerate the DSS workload. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 75

76 Chapter 5: XtremSW Cache Solution for Applications Table 7. XtremSW Cache deployment in a private cloud environment XtremSW Cache allocation per application/virtual machine ESXi 01 (allocation unit: GB) ESXi 02 (allocation unit: GB) Configuration details Oracle OLTP TB database under 1,800 Swingbench sessions DSS TB database with DSS workload SQL OLTP TB with OLTP workload SQL OLTP TB with OLTP workload Total Configuration of XtremSW Cache in the VMware environment The configuration of XtremSW Cache for a private cloud in a VMware environment needs to follow all the guidelines for each individual application, such as SharePoint, SQL Server, Exchange, and Oracle. For more information, refer to the EMC XtremSW Cache Installation and Administration Guide. Test results Test result for XtremSF in split mode used as the SQL Server tempdb for a DSS workload In the solution, a 200 GB XtremSW Cache was taken from the 700 GB XtremSF card and was used for the tempdb database data and log storage to accelerate performance. The SQL Server tempdb was heavily used as a temporary table store for sorting, row versioning, and so on. As the tempdb store for a DSS workload, the XtremSW Cache DAS can: Lower the peak latency of the tempdb data LUN from tens of milliseconds to less than 20 ms. Lower the average tempdb data LUN latency from tens of milliseconds to one ms. Test results for XtremSW Cache deduplication The test result shows: The Oracle deduplication hit ratio was about 4 percent. The SQL OLTP deduplication hit ratio was about 3 percent. The recommended deduplication settings for a structured database such as Oracle or SQL Server are: If the observed ratio is less than 10 percent, turn off the deduplication or reconfigure the deduplication gain to zero percent, to benefit from the extended cache device life. 76 EMC VSPEX with EMC XtremSF and EMC XtremSW Cache

77 Chapter 5: XtremSW Cache Solution for Applications If the observed ratio is over 35 percent, raise the deduplication gain to match the observed deduplication. If the observed ratio is between 10 and 35 percent, leave the deduplication gain as it is. Figure 40 shows that the deduplication hit ratio of SQL Server is 3 percent. Figure 40. Deduplication statistics for SQL Server OLTP Test results for two-tier storage Table 8 shows the performance summary for the private cloud environment. For Oracle, the response time dropped from 35 ms to 3 ms. For SQL Server, the response time dropped from over 20 ms to 3 ms. All database transaction rates improved, with the SQL Server OLTP gaining the most a three times transaction rate using part of the 700 GB caching space. The increased CPU usage was largely due to the increased workload. When the workload is kept the same or is not greatly increased, CPU usage does not increase much. This is seen in the case of ESXi 01, which hosts Oracle with only a moderate increase in the workload, the CPU usage did not greatly increase. EMC VSPEX with EMC XtremSF and EMC XtremSW Cache 77