Dell Compellent Storage Center

Transcription

1 1 of 8 Dell Compellent Storage Center Introduction The Compellent Storage Center is a block storage system aimed at the mid-tier enterprise market. The newest model is the SC8000 which replaces the earlier Model 40 although the Model 40 will continue to be available through Dell calls their design Fluid Data Architecture. Compellent calls their design Fluid Data Architecture. The concept of Fluid Data that is embodied with the architecture of the Compellent systems is that data can be automatically stored, moved, exported, or Highlights Dual controller block storage Virtualization of attached disks Thin Provisioning Snapshots Remote Replication Add-on NAS imported based on the intelligence in the Compellent system. The advanced features of the Compellent system are centered on managing and moving data to optimize the storage. The Compellent Storage Center is a dual controller design with redundant components that allow for failover in the case of failure of a controller and continued operation in the case of failure of other components. The dual controller system uses communication through switches to detect failure in the paired controller and handle the failover. Physical disks are virtualized with blocks to be stored or retrieved managed across the disks in virtual volumes. Using the indirection with the block locations not tied to specific disks prior to storing allows for the features such as automated tiering, use of all physical resources, and redistribution of data to avoid hotspots to be implemented. The virtualized architecture with blocks being handled independently also gives flexibility in handling of the RAID protection and the ability to do wide striping allowing for more simultaneous disk access. The cache management allows for multiple threads to access cache with read-ahead algorithm for read caching of data in system memory and a separate write cache mirrored across the controllers. The write cache is battery backed to maintain data in the case of a failure. I/O operations are monitored and optimized for performance by merging contiguous block requests into a single request to minimize physical disk revolutions, sorting I/O request to minimize seek operations, and deep tagged command queuing for multiple outstanding I/O requests to disks. Usage The Dell Compellent Storage Center system is a block storage device targeted for environments that have performance and advanced feature requirements typically in the mid-tier enterprise. Any application that requires block storage can use the Compellent system. The add-on NAS is a server with NAS software loaded and would be an independent NAS implementation.

2 2 of 8 Characteristics - Performance The Dell Compellent is a dual node, active-active system which should have good performance. No performance data has been made available at this time. - Availability The system is fully redundant with no single point of failure. The controller has an automated failover process. - Replication for BC/DR Asynchronous remote replication is available for BC/DR volume usages. Applications - The Dell Compellent Storage Center is targeted at applications that use block I/O. - The base set of included feature such as snapshot and remote replication are expected with tier 1 applications. The Dell system integrated with VSS for Windows environments. System environments - The Compellent Storage Center is a block storage system accessed using Fibre Channel and iscsi with standard drivers on host systems. Deployment and Administration - The Compellent system is known as an easy to install and easy to administer system. Customers should be able to install and configure the system or use services people from the reseller. Potential The Dell Compellent Storage Center is a modern architecture with virtualization of all attached storage and a sophisticated tiering implementation. Dell should be able to continue this architecture for a long time, adding more high value features such as synchronous replication, encryption and compression. Link to vendor site for specifications:

3 3 of 8 System Specifications from Evaluator Group Comparison Matrix Vendor System Basics Models Dell Compellent Storage Center SC8000 Cache Data Cache Max - per node 4 GB Number of Controllers 1, 2 Drive number - Max by Model Max physical capacity (Raw) Drives Currently Available FC Drives: 1,232 SAS Drives: 960 FC Drives: 739 TB SAS Drives: 960 TB Increment Dynamic Cache Partitioning System Cache - per node Not Applicable No GB SSD Max Drives / max capacity 480 / 96 TB Cache binding option Performance No SSD 200, 400 GB Total bandwidth (GB/sec) No Spec FC / SAS 15k 300, 600 GB 3.5" 146 GB 2.5" FC / SAS 10k 450, 600 GB 3.5" 450, 600, 900 GB 2.5" Max IOPS No Spec FATA, NL-SAS, SATA 7.2k NL-SAS 1, 2, 3 TB 3.5" 1 TB 2.5" SPC-1 No Drive intermix (per drive encl) RAID Configurations RAID Levels RAID Intermix Max drives per RAID group Global hot spare Redundant hot swap 0, 5, 6 (data initially written to RAID 10) Configurable SPC-2 LUN s Max LUN s / System Max LUN size Wide Striping No No Spec 10 PB

4 4 of 8 Dell Compellent Highlights Virtualization of the attached disk storage Wide-striping of data blocks across all physical disks Thin provisioning RAID protection levels 0, 10, 5, 6 Data prioritization control of service level assignment to prioritize data access Automated tiered storage called Data Progression 1 Dell Compellent Highlights Additional element to provide file access using NAS protocols Live Volume storage hypervisor to present storage volume to two storage arrays for workload migration and failover All disks in a single pool (virtualized) Data restriped across disks that are added size can be either 512K, 2 MB (default) or 4 MB

5 5 of 8 Compellent for Virtual Dell Compellent Model Comparison Feature / Function Model SC8000 Model 40 Form Factor Rack Mount Number of Controllers 1 or 2 (HA) with two 2.5 GHz 6-core 1 or 2 (HA) with single 2.5 GHz dualcore Xeon processors Xeon processors RAID Levels 0, 5, 6, 10 Maximum Disk Drives FC 1, drives per enclosure SAS and 24 drives per enclosure Minimum Disk Drives 2 Drive Sizes Supported SSD: 200, 400 GB SAS FC 3.5 : 300, 600 GB 15,000 RPM 450 GB 10,000 RPM SAS 3.5 : 450, 600 GB 15,000 RPM, 1, 2, 3 TB 7,200 RPM SAS 2.5 : 146 GB 15,000 RPM, 450, 600, 900 GB 10,000 RPM NL-SAS: 1 TB 7,200 RPM Maximum Raw Capacity FC: 739 TB SAS: 960 TB Disk Interface Speed FC: 4 Gb/s - 11 loops per chain SAS: 6 Gb/s 10 loops per chain Maximum backend ports FC 16, SAS 10 System Memory GB 12 GB NVRAM Capacity 512 MB 512 MB Drive intermix Drive spin-down No No Min/Max iscsi ports 0 / 10 0 / 10 Min/Max Fibre channel ports 0 / 16 0 / 16 Min/Max FCoE ports 0 / 10 0 / 10 Host Interface Fibre Channel 4, 8Gb/s; iscsi, 1Gb/s, 10Gb/s; FCoE 10Gb/s

6 6 of 8 Dell Compellent Advanced Features Snapshots with consistency groups Separate server with NAS software loaded is option Previous: Window-based and Open Solaris with ZFS Dell FS8600 NAS product front end Dell Compellent Advanced Features Data Instant Replay (Snapshot) copy on write Created on time interval No limit on number Remote Instant Replay (Replication) Asynchronous replication: full copy made and then incremental changes are replicated Can use FC or IP for replication

7 7 of 8 Dell Compellent Data Progression Architecture System captures in-depth access information Storage profile for SSD s required Supports 9 tiers of storage Based on 3 drive types, 3 rotation speeds, 3 RAID levels Based on System datapage size size can be either 512K, 2 MB (default) or 4 MB Data Progression Default is 3 days of learning move to promote data, 12 days for demotion Write cache should be disabled on SSD volumes Reports built-in to system, including amount of data to be moved up or down next cycle Considers RAID levels, and track placement as well Dell Compellent Data Progression Architecture System captures in-depth access information Storage profile for SSD s required Supports 9 tiers of storage Based on 3 drive types, 3 rotation speeds, 3 RAID levels Based on System datapage size size can be either 512K, 2 MB (default) or 4 MB Data Progression Default is 3 days of learning move to promote data, 12 days for demotion Write cache should be disabled on SSD volumes Reports built-in to system, including amount of data to be moved up or down next cycle Considers RAID levels, and track placement as well

8 8 of 8 Dell Compellent Strengths and Concerns Strengths Very economical system with advanced features only seen on more expensive systems Designed as a virtualized system Automated tiering data progression Dell will be able to push product and drive costs Ability to migrate volumes to other systems Potential Concerns Confusion between EqualLogic and Compellent Need some additions Larger cache Data reduction Encryption More detailed information is available at Copyright 2012 Evaluator Group, Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or stored in a database or retrieval system for any purpose without the express written consent of Evaluator Group Inc. The information contained in this document is subject to change without notice. Evaluator Group assumes no responsibility for errors or omissions. Evaluator Group makes no expressed or implied warranties in this document relating to the use or operation of the products described herein. In no event shall Evaluator Group be liable for any indirect, special, inconsequential or incidental damages arising out of or associated with any aspect of this publication, even if advised of the possibility of such damages. The Evaluator Series is a trademark of Evaluator Group, Inc. All other trademarks are the property of their respective companies.