WHITE PAPER STORNEXT STORAGE PLATFORM FOR MEDIA WORKFLOWS. Part 1: The StorNext File System

Transcription

1 WHITE PAPER STORNEXT STORAGE PLATFORM FOR MEDIA WORKFLOWS Part 1: The StorNext File System

2 CONTENTS Introduction... 3 The Challenges of Rapidly Evolving 21st-Century Workflows... 3 StorNext Platform for Data Management File System and Storage Topology Basics... 4 StorNext File System Offers Benefits of DAS, NAS, and SAN... 6 Benefits of the StorNext File System... 6 StorNext Production Storage Topology... 7 Tuning the StorNext File System for Optimal Performance... 8 Slicing and Striping... 9 StorNext 5 and Metadata Performance Summary WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

3 INTRODUCTION The two core requirements of video production storage systems have always been somewhat at odds. Editing and effects require the high-performance playback typically found in direct-attached storage (DAS). However, the collaborative nature of file-based media workflows, combined with the need to share large files rather than duplicate them, requires shared access. Network-attached storage (NAS) often uses IP-based file-sharing protocols that can be subject to network congestion and can fail to deliver the in-order deliver characteristics critical to frame-based editing. Quantum s StorNext file system gained popularity across the media and entertainment industries for its ability to resolve these differences. For almost two decades, Quantum s StorNext engineers develop media-specific storage technologies in lockstep with industry requirements. StorNext was the first widely adopted collaborative storage area network (SAN) environment to deliver predictable, real-time, performance for uncompressed standard-definition (SD) and highdefinition (HD) finishing. As industry demands on storage continued to grow, StorNext evolved providing seamless, automated data moving and archiving capabilities from high-speed primary production storage to nearline NAS, object storage, cloud archive, and tape. With 4K UHD, 8K, and virtual reality (VR) gaining popularity, performance and sharing requirements are only increasing. In preparation, Quantum rearchitected StorNext to take advantage of the latest multicore processing architectures, high-capacity system memory, and solid-state storage technologies. StorNext 5 further closed the performance/collaboration gap by adding support for multi-protocol NAS support, enabling users to connect more easily to highperformance StorNext environments with affordable Ethernet. THE CHALLENGES OF RAPIDLY EVOLVING 21ST-CENTURY WORKFLOWS The creation, distribution, and consumption of video content is increasing at a rate which was unimaginable 20 years ago. Advances in camera and screen resolutions, satellite, sensor, and seismic technologies are creating a massive influx of data that needs to be captured, processed, and preserved. Government agencies need shared access to data, so they can deliver increased situational awareness. Video content providers are challenged with 4K production on one end, and always-on devices that require more formats in more places on the other. Corporations are increasing their use of video to promote products and train employees, stressing traditional IT. The fact that data is being kept longer to be repurposed in the future combined with data growth and budget pressures leads to a need for high-performance, scalable storage that is also cost-effective. In recent years, the NAS or SAN debate has given way to more business-driven discussions regarding the ideal characteristics for data production and lifecycle management. While the priority differs among business sectors, the list is somewhat universal: Provide the fastest possible connection between applications and data Scale primary storage to massive capacities with no performance loss Provide flexible I/O, so solutions can be optimized for budgets and client performance requirements Support third-party project and asset management solutions via an open, robust API Maintain application accessibility to all data, forever. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 3

4 STORNEXT PLATFORM FOR DATA MANAGEMENT Connecting via fast Fibre Channel and Ethernet connections, StorNext volumes appear as a single, managed volume to the hundreds of Windows, Macintosh, and Linux-based applications used in content creation. The Quantum StorNext platform provides data management services through two distinct but integrated components: StorNext File System High-speed shared data access from primary storage from SAN and local-area network (LAN) connections StorNext Storage Manager Automated storage tiering, archiving, and data protection across a range of storage types This white paper focuses on the StorNext File System. StorNext File System High-performance data sharing with SAN/LAN access StorNext Storage Manager Tiered storage, archive, and data protection NFS CIFS STORNEXT SAN & LAN CLIENTS XSAN CLIENTS NFS & CIFS CLIENTS ETHERNET INFINIBAND FIBRE CHANNEL ISCSI STORNEXT PRIMARY STORAGE LATTUS EXTENDED ONLINE STORAGE STORNEXT VAULTING & ACTIVE VAULT TAPE ARCHIVES Q-CLOUD FILE SYSTEM AND STORAGE TOPOLOGY BASICS The StorNext File System enables collaborative workflows in which video, images, and analytical data can be shared and directly accessed simultaneously at high speed by multiple computers and servers (clients) across multiple operating systems. To appreciate the advanced capabilities of StorNext, it helps to understand the major types of storage file systems and storage topologies used today. A file system creates a hierarchy of data on storage devices and controls how data is written and read. File systems allocate and manage the storage blocks where data is written, store and retrieve the files requested by clients, enforce access control restrictions, and resolve access conflicts between clients to ensure data integrity. File system performance determines the ultimate performance of a storage system, based primarily on how efficiently it organizes its files and directory structures. Computer Operating File Systems on Direct-Attached Storage (DAS) Windows, Mac OS, Linux, or UNIX operating systems each have their own specific file system (NTFS, EXT3, FAT, HFS+). Typically, these operating systems run off direct-attached drives that are either physical or virtual. Sometimes USB or Thunderbolt-attached drives attach to these clients. DAS volumes are an extension of the operating system storage itself, and write at the block level of the host storage device(s) in their own particular manner. The downside of DAS storage is that is only available at peak speed to an individual client, which results in underutilized storage capacity and the need to copy files back and forth between collaborators. 4 WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

5 Direct Attached Storage (DAS) WORKSTATION OR SERVER SCSI RAID STORAGE Network-Attached File System (NAS) In many business environments, files are shared between clients using a file system running on a NAS appliance. NAS volumes are viewed by clients as a different file system than its own. NAS volumes appear to clients as a file server. To access NAS files, clients use networking protocols such as NFS or SMB using affordable Ethernet connections. Although affordable, in a NAS environment, files must be copied from the data storage to the NAS server s memory before it can transmit the information to the requestor. This requires files to be converted into Internet Protocol (IP) packets before they can do so. The time it takes to do this (latency) can go unnoticed in word processing or operation. In serving HTML content, the latency is widely accepted. However, for operations such as financial transactions, video processing, and visualization, these performance fluctuations can be disruptive. Network Attached Storage (NAS) CLIENTS CLIENTS ETHERNET SWITCH FILE SERVER WITH STORAGE CLIENTS In addition to latency, IP protocols do not preserve in-order packet delivery. In a video workflow, this is especially critical. If video frames arrive out of order from the storage to a client performing a playout, the client will have to reorder the data before it can continue the stream. For media applications, this is a common cause of dropped frames. Improvements in Ethernet technology have allowed acceptable remote file-processing performance on NAS for some use cases. However, latency is still common when multiple clients request concurrent access to larger files over Ethernet, or when there is great disparity between the file sizes being accessed. Storage Area Network (SAN) Shared File Systems A SAN is a purpose-built distributed peerto-peer file system between client storage. No file server is needed as a middleman. A SAN storage volume appears to every client as an extension of its own file system. Files are written quickly to the block level of the fast storage arrays using SCSI commands at DAS-or-better performance. There is no latency from file-level IP operations. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 5

6 In a standard SAN, each client gets its own allocation of storage and dedicated bandwidth. In a shared SAN (or clustered SAN), the file allows multiple clients to access a shared pool of storage. In this type of SAN, multiple clients have access to the same blocks on the same volume. The metadata controller acts as a traffic cop, managing file locking, space allocation, and data access authorization. Standard SAN StorNext SAN APPLICATION APPLICATION APPLICATION APPLICATION METADATA CONTROLLER FILE SYSTEM FILE SYSTEM FILE SYSTEM FIBRE CHANNEL FIBRE CHANNEL CLIENT A STORAGE CLIENT B STORAGE ALL CLIENTS SHARE STORAGE In a standard SAN, storage is dedicated to each client. In a StorNext SAN, a metadata controller manages storage allocation, bandwidth, file sharing for all clients. However, unlike a NAS server, the metadata controller handles only a file s structural metadata. The actual user data travels on a separate path via block-based Fibre Channel or Ethernet protocols. Eliminating file server bottleneck between client and storage and freeing smaller metadata operations from larger user data I/O are key to SAN file systems outperforming NAS. STORNEXT FILE SYSTEM OFFERS BENEFITS OF DAS, NAS, AND SAN StorNext File Systems enable shared SAN environments that use Fibre Channel connections to process and deliver data frames at a guaranteed speed in guaranteed order. For cost and access flexibility, a scale-out NAS gateway can provide affordable shared Ethernet access to the same pool of high-speed storage. StorNext also features an optional IP-based block-based Distributed LAN Client (DLC) with guaranteed in-order frame delivery over 1Gb, 10Gb, and 40Gb Ethernet. BENEFITS OF THE STORNEXT FILE SYSTEM Fibre or IP connections to Linux, Mac, Windows, and UNIX clients under a single namespace Multi-protocol access for flexible connectivity High-performance, scalable UNIX-based architecture easily supports heavy data loads Out-of-band, direct-access to Fibre, iscsi, and InfiniBand for peak performance Fibre connection between NAS and SAN storage eliminates data movement over the LAN 6 WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

7 Fibre or IP Connections to Linux, Mac, Windows, and UNIX Clients XCELLIS WORKFLOW DIRECTORS STORAGE IP Data Path IP Data and Metadata Path Fibre Channel Data Path DLC CLIENTS NAS CLIENTS STORNEXT PRODUCTION STORAGE TOPOLOGY The speed at which files can be stored or retrieved is not only a function of physical storage performance, but also how efficiently the files structural metadata is stored. Structural metadata is information about the user data that is being stored, such as where files are in a directory, their creation data and access permissions. Metadata is used for all indexing and searching of content and is updated whenever a file is created, deleted, modified, or accessed. Metadata space requirements are typically a fraction of the size of the data itself. Separating user data and metadata operations is a key design feature that makes StorNext so extraordinarily responsive. For example, metadata can be stored on solid-state disk drives, which provide excellent random I/O performance for small data operations. Large user data files, such as video files or application datasets, can then be written simultaneously at block-level speeds across more affordable standard disks, where redundant array of independent disks (RAID) arrays spread file segments across multiple drives, aggregating drive performance and providing protection against data loss. Metadata is typically processed over a dedicated Gigabit Ethernet LAN connection using two, redundant metadata controllers (MDCs) running on Xcellis Workflow Directors. User data is processed at block level over Fibre Channel or Ethernet (iscsi, InfiniBand, or Quantum s blockbased DLC). StorNext utilizes one or more Fibre Channel connections on between the client and the storage array(s). The clients are connected to the storage array while metadata traffic is kept on a separate Ethernet connection, thus out of band from the data transfer itself. The MDCs ensure that all files can be read at the same time from multiple clients, but not overwritten. This unique design scales performance from a few gigabytes per second to hundreds by aggregating the performance of up to hundreds of disk arrays and thousands of disks. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 7

8 1. Client application issues a command to the StorNext client, which is sent to Metadata Controller via the LAN. 3. StorNext clent receives block and performs I/O operation directly to array without an in-band bottleneck, allowing maximum data speed. 2. Metadata Controller processes and responds back to client via LAN with disk blocks location for data read or write. RAID 6 LUN The following summarizes the communication sequence between a StorNext client and the MDC: 1. Client application issues a command to the StorNext client, which is sent to MDC via the LAN. 2. MDC processes and responds back to client via LAN with the disk block locations for data read or write. 3. StorNext client receives block and performs I/O operation directly to disk array without an in-band bottleneck, allowing data to be transferred at the maximum possible speed. TUNING THE STORNEXT FILE SYSTEM FOR OPTIMAL PERFORMANCE StorNext File System clients access files from high-performance storage arrays. One reason StorNext is unique among shared file systems is the degree to which the configuration of these arrays can be finely tuned to different workflow requirements. The following outlines the basic components of the SNFS and the benefits of being able to adjust the corresponding parameters: LUNs and Data Stripe Groups Configuring StorNext for optimal performance starts with the creation of logical unit numbers (LUNs). A LUN is a virtualized group of two or more drives combined into a RAID arrays. Different RAID levels are used for different types of data (see diagram). LUNs are then aggregated into stripe groups, which are virtualized storage pools aggregated together to increase system performance. StorNext performance can be tuned by controlling the size and settings of LUNs and stripe groups. 8 WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

9 Video Other STORNEXT VOLUME Audio Folder Affinities Metadata and Journal High- Availability 4K HD Affinity Tags Stripe Groups Data Striping Across LUNs RAID-based LUNS RAID 10 RAID 1 RAID 6 RAID 6 RAID 6 RAID 6 RAID 6 RAID 6 In this example, the StorNext file system has a single RAID 1 LUN for metadata and journal information, a RAID 10 LUN for high-availability protection of the metadata controllers, four RAID 6 LUNs aggregated into two stripe groups for very high performance such as 4K video, and another stripe group with slightly less performance for less intensive applications. Affinities can be assigned to designate the data with the most intensive bandwidth needs be written to the appropriate LUNs. Affinities Based on file-name extensions, data of a specific type may also be assigned to a given stripe group using affinities. For example, audio files could be steered to a stripe group with a 300MB/s performance while 4K video files could be steered to a stripe group with a 2GB/s performance. SLICING AND STRIPING Another way to maximize performance is to create LUNs with similar performance characteristics. In normal drive striping, performance decreases as drives fill up. This is because the inner part of disk drives reads and writes slower than the outer parts. StorNext allows LUNs to be sliced, which allows for the creation of stripe groups with similar speed characteristics, which can then be matched to performance characteristics of data. Standard Striping All areas of all drives are striped together. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 9

10 LUN Slicing LUN3/Slice 3 - Slowest Performance LUN2/Slice 2 - Good Performance LUN1/Slice 1 - Best Performance StorNext allows LUNs to be sliced, which allows for the creation of stripe groups with similar speed characteristics. Stripe groups can be configured for holding three different types of data: Metadata and journaling information Metadata (as described above) and journaling information that tracks file system transactions for purpose of recovery High-availability data backup Data used to support the functionality of redundant metadata controllers User data The performance of which can be further optimized by some of the additional parameters outlined below. Stripe Breadth Stripe breadth is defined as the amount of data written to a given LUN before writes are transitioned to the next volume. A small stripe breadth is optimal for smaller I/O operations or compressed video files. Larger stripe breath optimizes performance for larger files and uncompressed video processing. Video Other SAN VOLUME Audio Folder Affinities Metadata and Journal Video Video Audio Other Affinity Tags Storage Pools Data Striping Across LUNs RAID Arrays (LUNS) RAID 1 RAID 5 RAID 5 RAID 5 RAID 5 RAID 5 RAID 5 RAID 0 10 WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

11 Allocation Session Reservation ASR allows users to write individual files that will be read in sequence to be kept together. This decreases the random access seek time and increases playback performance. This feature is particularly important for high-resolution video workflows when every video frame is captured as a single, uncompressed file. Client-Side Mount Options StorNext clients use local caching to improve performance and reduce the amount of communication between the client and the metadata controller. The amount and types of client caching are tunable per client and per file system. Mount options also exist to control certain client behavior, such as whether to write ATIME or access time of a file. Mount options for controlling buffer cache behavior can be used to customize performance for a specific workload. Metadata Buffer Cache StorNext 5 has a sophisticated multi-stage caching algorithm for metadata inside the metadata controller. The caching system will use system memory to hold metadata. When held in cache, metadata lookups occur at the fastest possible speeds. With advanced metadata techniques, including metadata compression, StorNext 5 can cache metadata for millions of files without needing to read from a disk array. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 11

12 STORNEXT 5 AND METADATA PERFORMANCE Historically, the StorNext File System provided fast performance for a wide variety of workflows, the key to which has always been metadata performance. In 2014, Quantum released StorNext 5. Four years in the making, StorNext s metadata and journaling architecture was entirely rewritten to take advantage of modern multi-core and multi-threaded processors and large memory architectures. The redesigned metadata layout greatly reduces the latency of file system operations while also operating more efficiently with multi-threaded applications. Larger block allocation boosted supported file count (to multi-petabyte levels) and the number of clients to be connected. A higher-density cache keeps more metadata in memory for easier operations on large data sets. A further boost was added by rewriting metadata journaling to take advantage of the blinding performance of solid-state disks. StorNext 5 delivered file performance improvements of 5 to 10 times over the previous generation and 10X improvement on the number of files supported (up to 10 billion). File fragmentation was drastically reduced. Performance of larger sized files increased. IOP performance also improved through faster create, delete, and lookup operations. Read/write operations and caching were improved to take full advantage of solid-state drives and larger pools of random-access memory. Eliminating Fragmentation The majority negative impact from file fragmentation was virtually eliminated in StorNext 5 through a unique combination of new on-disk file structuring, improved caching techniques, and enhanced metadata tracking capabilities. Major Improvements in Small File Performance Support for larger sized files increased, but so too did performance for small file operations (IOPS). Users of StorNext in media and entertainment have been quick to embrace StorNext 5 for typically IO bound applications such as visual effects and animation rendering. Those in financial analytics, oil and gas, and life sciences that need high-performance computing and data analysis also found significant improvement. Combined with the added InfiniBand support and its microsecond latencies, and flexible and affordable NAS, StorNext 5 set the foundation for a new generation of performance for one of the world s most trusted data management platforms. StorNext 5 Performance Testing Results Files/Second Write of 100,000 Files 1K 2K 4K 8K 16K 32K 64K 128K 256K 512K 1024K StorNext 4.3 StorNext 5 12 WHITE PAPER StorNext Storage Platform for Media Workflows: The StorNext File System

13 SUMMARY Media workflows have always been among the most demanding applications for storage. New advances in resolution, color depth, and frame rates have placed even more demands on performance and scalability, especially in content creation, which is an inherently a collaborative process. The StorNext File System meets these demands by enabling team members and applications to share video, images, and analytical data by directly accessing the files simultaneously at high speed from clients running multiple operating systems. By allowing data to be accessed across NAS as well as shared SAN connections, it serves the full range of media workflow functions from the streaming performance-intensive editorial operations to rendering, transcoding, and other operations better suited for running across IP connections. To further meet the unique needs of media, the StorNext File System can also be tuned to meet specific performance requirements for a variety of data patterns, such compressed versus uncompressed file sizes or by directing files to the best storage type for its file type. With the release StorNext 5, Quantum engineers reworked the StorNext File System to increase its scalability and performance to meet the evolving needs of media workflows. Quantum is committed to continuing development so that StorNext will remain the media and entertainment industry s leading open storage platform. StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 13

14 ABOUT QUANTUM Quantum is a leading expert in scale-out storage, archive and data protection. The company s StorNext 5 platform powers modern high-performance workflows, enabling seamless, real-time collaboration and keeping content readily accessible for future use and re-monetization. More than 100,000 customers have trusted Quantum to address their most demanding content workflow needs, including top studios, major broadcasters and cutting-edge content creators. With Quantum, customers have the end-to-end storage platform they need to manage assets from ingest through finishing and into delivery and long-term preservation. See how at Quantum Corporation. All rights reserved. WP00220A-v01 Oct 2016 StorNext Storage Platform for Media Workflows: The StorNext File System WHITE PAPER 14