IBM System Storage Reference Architecture featuring IBM FlashSystem for SAP landscapes, incl. SAP HANA

IBM System Storage Reference Architecture featuring IBM FlashSystem for SAP landscapes, incl. SAP HANA IBM SAP International Competence Center, IBM Germany Version 1.3, September 2015 isicc@de.ibm.com This document is available on http://www-03.ibm.com/support/techdocs/atsmastr.nsf/webindex/wp102361 Contents 1. Overview... 2 2. Storage technologies, latency, and performance... 2 3. Business value of IBM FlashSystem... 4 4. Storage virtualization with IBM Spectrum Virtualize (SVC)... 5 5. IBM Easy Tier manages hot data and cold data fully automated... 6 6. Virtualized storage infrastructure for SAP landscape... 7 7. Backup and recovery through IBM Spectrum Protect... 8 8. Maximum IO performance with IBM SVC and IBM FlashSystem... 10 9. Standard SAP operations eased with IBM Spectrum Virtualize... 10 10. Discussion on full in-memory technology vs. classical implementation 11 11. IBM FlashSystems 900 and V9000... 12 12. Resources... 12 13. Notices... 13 14. Trademarks... 15 Copyright IBM Corporation 2014

1. Overview This Whitepaper describes the storage reference architecture featuring flash technology for SAP landscapes, why flash technology is being used, and how it can be integrated with an (existing) SAP / IT infrastructure. This paper also discuss the pros & cons of pure in-memory technology like SAP HANA versus the classical approach with relational databases and the usage of flash technology. 2. Storage technologies, latency, and performance Storage systems (for data bases) have to serve several aspects: In addition to availability and reliability, they need to meet specific performance requirements: 1. Performance: Number of IO per second 2. Throughput: Number of MB per second 3. Latency: Response time of a single IO While almost all storage system can achieve high performance and high throughput with HDD, it needs special technology to achieve low latency, needed especially for random IO workload with small data block size the typical SAP Business Suite workload. OLTP and OLAP are suffering from high IO latency, batch jobs may have a long run time. Figure 1 shows the typical points that add to latency for various types of storage technologies. Figure 1: Latency of different storage technologies DRAM has the lowest latency, but is the most expensive storage device. Typically Flash technology has 10 to 50 times less latency then HDD. Copyright IBM Corporation 2015 Page - 2

By comparing one SSD with one HDD, or one SSD RAID with one HDD RAID, an SDD device always performs faster than an HDD device, and Flash always performs faster than an SSD. This is especially true for OLTP, which is critical for SAP applications. Flash technology has the highest performance advantage on random read workload here, in contrast, HDDs need to re-position the read/write head for every data block, leading to a long latency. With random read workload Flash technology delivers typically 10 to 20 times less latency. Figure 2 illustrates the I/O service time of HDD. Figure 2: IO response time with HDD Issue I/O request ~ 100 μs Wait for I/O to be serviced ~ 4,000 μs Process I/O ~ 100 μs Time to process 1 I/O request = 200 μs + 4,000 μs = 4,200 μs Figure 3 illustrates the I/O service time of Flash Figure 3: IO response time with Flash Issue I/O request ~ 100 μs Wait for I/O to be serviced ~ 100 μs Process I/O ~ 100 μs Time to process 1 I/O request = 200 μs + 100 μs = 300 μs Copyright IBM Corporation 2015 Page - 3

Considering price per TB (terabyte), FlashSystem storage (or SSD) are more expensive than HDD. However, if speed is important, Flash configurations are cheaper. Figure 4: Price / performance of Flash (SSD) and HDD 3. Business value of IBM FlashSystem IBM FlashSystem storage systems deliver high performance at an economical price, helping to address performance issues with business critical application, and can either complement or replace traditional hard disk arrays in Online transaction processing (OLTP) or Online analytical processing (OLAP). FlashSystem products increase application performance as much as 10x faster than HDD storage solutions. When compared to equivalent disk systems, IBM flash memory solutions deliver capacity in a quarter floor space comparing to HDD storage systems. These solutions include the latest in industry-standard, solid-state flash memory technology, including enterprise multi-level cell (emlc) flash technology and single-level cell (SLC) flash technology. Data is moved through the system as quickly as possible, with no bottlenecks. FlashSystem products have durable and reliable design that use enterpriseclass flash technology and patented data-protection technology like Variable Copyright IBM Corporation 2015 Page - 4

Stripe RAID (VSR ), 2D flash RAID, Active Spare support, error correction code (ECC) at the chip level, and other reliability technologies. Two-dimensional flash RAID eliminates single points of failure and provides enhanced system-level reliability. VSR technology helps reduce business interruptions and prevent chip failures to enhance the two-dimensional protection mechanism. It also maintains performance capacity levels. Hot-swappable flash modules and redundant components with built-in battery backup help boost data availability and IT productivity. An available integrated spare flash card limits downtime. 4. Storage virtualization with IBM Spectrum Virtualize (SVC) IBM Spectrum Virtualize, also known as IBM SAN Volume Controller (SVC), a member of the IBM Storwize family, is a storage virtualization system with a single point of control for storage resources. SVC improves business application availability and delivers higher resource utilization, helping to achieve a simpler, more scalable and cost efficient IT infrastructure. Virtualizing storage with IBM Spectrum Virtualize helps make new and existing storage more effective. SVC includes many functions traditionally deployed separately in disk systems. By including these in a virtualization system, SAN Volume Controller standardizes functions across virtualized storage for greater flexibility and potentially lower costs. Every storage virtualized by IBM Spectrum Virtualize benefits from the virtualization functionality. For example, Easy Tier optimizes the use of flash storage. And Real-time Compression enhances efficiency even further by enabling the storage of up to five times as much active primary data in the same physical disk space. Finally, high-performance thin provisioning helps automate provisioning. These benefits can help extend the useful life of existing storage assets, reducing costs. Thin provisioning to allocate storage just-in-time : Improved utilization by pooling all physical storage capacity IBM Easy Tier for storage efficiency IBM FlashCopy for point-in-time copies in combination with IBM Spectrum Protect (Tivoli Storage FlashCopy Manager, IBM FCM). High availability features through mirroring and copy services for data replication and protection Real-time compression Copyright IBM Corporation 2015 Page - 5

5. IBM Easy Tier manages hot data and cold data fully automated. Hot data is frequently accessed data, and the amount of data is too large to fit in any cache. Migrating it from HDD to SDD or to FlashSystem storage can provide significant performance improvement. Cold data is less frequently accessed data or data that is not accessed at all. Migrating it from HDD to SSD might provide little or no benefit. Easy Tier assumes that sequential workloads will not benefit from flash technology significantly, and that HDD/ SAS disks are good candidates for data that is primarily accessed sequentially. IBM Easy Tier enables more effective storage consolidation by eliminating the manual placement of data (files or file system) on Flash & HDD. Easy Tier automatically and dynamically moves the appropriate data to the appropriate storage tier, based on ongoing performance monitoring. Easy Tier performs data relocation within SSD/FLASH and HDD storage pools (also referred to as a hybrid solution) to achieve the optimum performance, by moving hottest extents to FLASH/SSD, and cooler extents to HDD. It is done automatically, dynamically, and transparently to hosts, that is, without disruption to applications. This feature significantly improves the overall storage cost performance and simplifies the performance tuning and management. Figure 5: Easy Tier manages hot and cold data Copyright IBM Corporation 2015 Page - 6

6. Virtualized storage infrastructure for SAP landscape The following figure shows how Flash is integrated and used for SAP data bases. The underlying method of storage pooling and Easy Tier applies not only to SAP application, but to any application with a similar workload like OLAP or OLTP, e.g. Email systems. Figure 6: Integration of IBM FlashSystem into SAP landscapes Basically three pools needs to be configured on SVC: Flash only pool: All SAP production data bases with a high IO/s requirement (IO/s per TB) will be put into tis pool. Here high IO requirement means high IO per second per Terabyte. Easy Tier pool: All remaining SAP production data bases will be put into this pool. Easy Tier will identify the hot spots and move them to Flash/SSD storage. HDD only Pool will be used for all remaining SAP applications, typically Development and Test systems, with a (high) capacity, but low performance demand. This 3-tier pool concept does not any apply to SAP application in principle it is applicable to the entire IT landscape. The HDD capacity can be built from any IBM SAN attached storage system, like IBM DS8000 System Storage, IBM XIV System Storage, or IBM Storwize family with V7000, V5000, or V3700. Copyright IBM Corporation 2015 Page - 7

The following table provides three sample configuration for a given performance and capacity requirements for a SAP landscape, by using IBM Storwize V7000 and IBM FlashSystem 900. The configuration does not include mirroring. For detailed planning please contact your IBM sales representative, IBM Business Partner, or send an email to isicc@de.ibm.com. Capacity & Performance Storwize V7000 HDD config each FlashSystem 900 config each SVC config HDD only config each 50 TB & 50.000 IO/s 1 * V7000 80 * 600 GB HDD 1 * 900 12 * 1.2 TB 2 * nodes 1 * V7000 300 * 600 GB HDD 100 TB & 100.000 IO/s 1 * V7000 160 * 600 GB HDD 1 * 900 12 * 2.7 TB 2 * nodes 2 * V7000 300 * 600 GB HDD 500 TB & 500.000 IO/s 2 * V7000 250 * 1.2 TB HDD 2 * 900 12 * 5.7 TB 6 * nodes 8 * V7000 300 * 600 TB HDD Table 1: Sample storage configurations for SVC By introducing flash technology the number of storage systems and the number of HDD can be reduced significantly, from 10 systems with 3000 HDD total down to 2 systems with 500 HDD total (third config), by increasing IO performance, and reducing latency. 7. Backup and recovery through IBM Spectrum Protect IBM Spectrum Protect, also known as IBM Tivoli Storage Manager (TSM), is a data protection platform that gives SAP customer a single point of control and administration for storage management needs. It enables outstanding efficiency, simplicity and scalability for virtual, physical and cloud backup environments of all sizes. IBM Tivoli Storage FlashCopy Manager (FCM) delivers high levels of protection for key applications and databases using integrated application snapshot backup and restore capabilities. Tivoli Storage FlashCopy Manager integrates with SAP, Data Bases and storage system snapshot technology to help create a high performance, low impact solution for advanced data protection. IBM Tivoli Storage Manager for Enterprise Resource Planning (TSM for ERP) protects vital SAP system data. It provides automated data protection designed for SAP and SAP HANA environments. TSM for ERP will help to improve the availability of SAP database servers and reduce administration workloads. Copyright IBM Corporation 2015 Page - 8

Figure 7: Backup and recovery through TSM Figure 7 illustrates the backup and recovery concept of SAP instances with TSM. For data base online backup through TSM for Data Base and TSM for ERP FlashSystem will help to achieve constant IO performance, enabling SAP end users to work without performance impacts while the backup process is running. To reduce the backup time significantly FCM can be used that will shrink down the backup process to a few seconds. The FlashCopy will be performed on the virtual volumes of SAN Volume Controller. Online backup as well as FlashCopy backup is available for IBM DB2, Oracle and Microsoft SQL server. TSM for SAN enable a LAN free backup, all date for backup or restore will be transferred through the SAN network, no backup (or restore) data is send through the LAN network. SAP HANA can be protected through TSM for ERP. Copyright IBM Corporation 2015 Page - 9

8. Maximum IO performance with IBM SVC and IBM FlashSystem Table 2 shows the achievable performance with IBM FlashSystem 820 and IBM SVC. The RedPaper IBM SAN Volume Controller and IBM FlashSystem 820 Best Practices and Performance Capabilities provides the full report. 2 Node & 1 Flash 4 Node & 2 Flash 8 Node & 4 Flash Read miss IO/s 390.000 680.000 1.500.000 Write miss IO/s 270.000 500.000 1.000.000 70/30 miss IO/s 360.000 620.000 1.300.000 Read miss MB/s 3.000 6.500 13.000 Write miss MB/s 2.400 4.800 9.700 Table 2: Performance values for FlashSystem and SVC For OLTP workload a performance of more than one million IO per second is achievable with just four Flash systems, in total 4 U high. The model 840 and 900 delivers more than 500.000 IO/s OLTP per system. 9. Standard SAP operations eased with IBM Spectrum Virtualize IBM Spectrum Virtualize (SVC) eases SAP operations and infrastructure administration: From on OS or server point of view just one type of storage device driver is required, delivered by any UNIX, LINUX or Microsoft based operation system. Adding new or replacing existing storage is transparent to the OS and application, and can be done without any downtime. This is true for storage maintenance as well. Adding IBM FlashSystem storage to SVC is transparent to the application, except that the application experience a lower IO response time. No manual data, storage, or LUN configuration is necessary; this will be done fully automated through IBM Easy Tier. Copyright IBM Corporation 2015 Page - 10

DB backup will remain unchanged, if DB on-line backup is used, e.g. with IBM Tivoli Storage Manager for ERP (TSM 4 ERP) or can be enhanced and speedup through SVC FlashCopy in combination with IBM Tivoli Storage FlashCopy Manager (TSM FCM), supporting IBM DB2 Oracle, and MS SQL data bases. IBM LVM is fully supported by SAP NetWeaver Landscape Virtualization Manager (SAP LVM), and simplifies operations like SAP homogeneous system copy, SAP copy or clone process. Even without SAP LVM the IBM SVC virtualization solution eases the process of copying SAP data bases through Flash- Copy thin or full provisioned. 10. Discussion on full in-memory technology vs. classical implementation There is no question that in-memory technology delivers very fast query results for Business Analytic workloads, and SAP HANA as well as IBM DB2 BLU addresses performance, performance, performance... There is a huge discussion going on, supported by analysts, whether SAP HANA is ready for enterprise/oltp or not, whether IBM DB2 BLU is faster or slower comparing to SAP HANA... This paper is not going to join this discussion. As with every major change within an SAP landscape, like replacing the data base from vendor A with vendor B, changing the server architecture from type X to type Y, there is a risk associated with it, and a price tag. The question to be discussed here: are there standard, easy to implement alternatives that will improve performance with less or no risks, not changing the standard, established, operation model, but delivering significant performance improvements. Here a list of item to consider: Flash technology delivers much faster IO response time, very low latency, comparing to HDD. The integration of Flash technology with IBM is fully transparent to SAP, no operational mode is affected. IBM customers have experienced a SAP batch run time improvement of factor 10. Upgrading and right-sizing the existing server to the latest technology level. IBM customers have experienced a SAP batch run time improvement of factor 10 by e.g. upgrading from IBM Power 5 to IBM Power 7 technology. Upgrading the data base level to benefit from IBM in-memory technology with IBM DB2 10.5 BLU. This is a standard DB upgrade. IBM customers have experienced SAP query time improvements of factor 4 to 40. Copyright IBM Corporation 2015 Page - 11

These three alternatives should be considered, because implementing them are just an upgrade, not a replacement, and could lead to significant performance improvements, while keeping the architecture of the SAP infrastructure unchanged. 11. IBM FlashSystems 900 and V9000 To build a sustainable advantage in a world of 24x7 continuous operations, today s enterprise organizations must be able to extract the full value of their vast and complex data sets. Because data is the new business currency, organizations must quickly and efficiently transact, analyze and gain actionable insight from it to fully capitalize on its value. The IBM FlashSystem family empowers organizations to take advantage of best-in-breed solutions that provide extreme performance, macro efficiency and microsecond response times. As a result, these organizations can quickly harness the value of stored data and be better positioned to compete, innovate and grow in today s real-time world. The FlashSystem 900 is a standalone storage system, and can be scaled up to >50 TiB usable capacity with RAID 5 protection. The FlashSystem V9000 is an integrated solution of IBM FlashSystem 900 and IBM SVC as one product, scalable up to 450TiB internal, usable Flash capacity, and delivers the same storage functionalities and storage virtualization functions like SVC. For more information please visit: http://www-03.ibm.com/systems/storage/flash/solutions/index.html 12. Resources IBM FlashSystem family product page http://www.ibm.com/storage/flash IBM Storwize family product page http://www-03.ibm.com/systems/storage/disk/storwize_v7000/index.html http://www-03.ibm.com/systems/storage/disk/storwize_v5000/index.html IBM SAN Volume Controller SVC http://www-03.ibm.com/systems/storage/software/virtualization/svc/index.html IBM FlashSystem in OLTP Database Environments http://www.redbooks.ibm.com/abstracts/tips0973.html?open Copyright IBM Corporation 2015 Page - 12

Implementing the IBM SAN Volume Controller and FlashSystem 820 http://www.redbooks.ibm.com/abstracts/sg248172.html?open IBM DB2 with in memory features http://www-01.ibm.com/software/data/db2/ 13. Notices This information was developed for products and services offered in the U.S.A. IBM may not offer the products, services, or features discussed in this document in other countries. Consult your local IBM representative for information on the products and services currently available in your area. Any reference to an IBM product, program, or service is not intended to state or imply that only that IBM product, program, or service may be used. Any functionally equivalent product, program, or service that does not infringe any IBM intellectual property right may be used instead. However, it is the user's responsibility to evaluate and verify the operation of any non-ibm product, program, or service. IBM may have patents or pending patent applications covering subject matter described in this document. The furnishing of this document does not grant you any license to these patents. You can send license inquiries, in writing, to: IBM Director of Licensing, IBM Corporation, North Castle Drive, Armonk, NY 10504-1785 U.S.A. The following paragraph does not apply to the United Kingdom or any other Country where such provisions are inconsistent with local law: INTERNATIONAL BUSINESS MACHINES CORPORATION PROVIDES THIS PUBLICATION "AS IS" WITH- OUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABIL- ITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states do not allow disclaimer of express or implied warranties in certain transactions, therefore, this statement may not apply to you. This information could include technical inaccuracies or typographical errors. Changes are periodically made to the information herein; these changes will be incorporated in new editions of the publication. IBM may make improvements and/or changes in the product(s) and/or the program(s) described in this publication at any time without notice. Any references in this information to non-ibm websites are provided for convenience only and do not in any manner serve as an endorsement of those Copyright IBM Corporation 2015 Page - 13

websites. The materials at those websites are not part of the materials for this IBM product and use of those websites is at your own risk. IBM may use or distribute any of the information you supply in any way it believes appropriate without incurring any obligation to you. Any performance data contained herein was determined in a controlled environment. Therefore, the results obtained in other operating environments may vary significantly. Some measurements may have been made on development-level systems and there is no guarantee that these measurements will be the same on generally available systems. Furthermore, some measurements may have been estimated through extrapolation. Actual results may vary. Users of this document should verify the applicable data for their specific environment. Information concerning non-ibm products was obtained from the suppliers of those products, their published announcements or other publicly available sources. IBM has not tested those products and cannot confirm the accuracy of performance, compatibility or any other claims related to non-ibm products. Questions on the capabilities of non-ibm products should be addressed to the suppliers of those products. This information contains examples of data and reports used in daily business operations. To illustrate them as completely as possible, the examples include the names of individuals, companies, brands, and products. All of these names are fictitious and any similarity to the names and addresses used by an actual business enterprise is entirely coincidental. COPYRIGHT LICENSE: This information contains sample application programs in source language, which illustrate programming techniques on various operating platforms. You may copy, modify, and distribute these sample programs in any form without payment to IBM, for the purposes of developing, using, marketing or distributing application programs conforming to the application programming interface for the operating platform for which the sample programs are written. These examples have not been thoroughly tested under all conditions. IBM, therefore, cannot guarantee or imply reliability, serviceability, or function of these programs. Copyright IBM Corporation 2015 Page - 14

14. Trademarks IBM, the IBM logo, and ibm.com are trademarks or registered trademarks of International Business Machines Corporation in the United States, other countries, or both. These and other IBM trademarked terms are marked on their first occurrence in this information with the appropriate symbol ( or ), indicating US registered or common law trademarks owned by IBM at the time this information was published. Such trademarks may also be registered or common law trademarks in other countries. A current list of IBM trademarks is available on the Web at http://www.ibm.com/legal/copytrade.shtml The following terms are trademarks of the International Business Machines Corporation in the United States, other countries, or both: DB2, DS8000, Easy Tier, FlashCopy, FlashSystem, IBM, IBM FlashSystem, Storwize, System Storage, System x, XIV The following terms are trademarks of other companies: VSR, and the Texas Memory Systems logo are trademarks or registered trademarks of Texas Memory Systems, an IBM Company. Microsoft, and the Windows logo are trademarks of Microsoft Corporation in the United States, other countries, or both. SAP, and the SAP logo are trademarks of the SAP AG, Germany, other countries, or both. Other company, product, or service names may be trademarks or service marks of others. Copyright IBM Corporation 2015 Page - 15