Array Tuning Best Practices A Dell Technical White Paper

PowerVault™ MD3200 and MD3200i Storage Arrays

PowerVault™ MD3200 and MD3200i: Array Tuning Best Practices

THIS WHITE PAPER IS FOR INFORMATIONAL PURPOSES ONLY, AND MAY CONTAIN TYPOGRAPHICAL ERRORS AND TECHNICAL INACCURACIES. THE CONTENT IS PROVIDED AS IS, WITHOUT EXPRESS OR IMPLIED WARRANTIES OF ANY KIND. © 2010 Dell Inc. All rights reserved. Reproduction of this material in any manner whatsoever without the express written permission of Dell Inc. is strictly forbidden. For more information, contact Dell. Dell, the DELL logo, and the DELL badge, PowerConnect, and PowerVault are trademarks of Dell Inc. Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. Dell Inc. disclaims any proprietary interest in trademarks and trade names other than its own.

June 2010

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PowerVault™ MD3200 and MD3200i: Array Tuning Best Practices

Contents Audience and Scope .................................................................................................... 2 Performance Tuning Overview ....................................................................................... 2 Components That Influence Storage Performance ............................................................. 2 Basic Approach to Performance Tuning .......................................................................... 2 Application Software Considerations ............................................................................. 3 Configuring the PowerVault™ MD3200 and MD3200i Series of Arrays .......................................... 3 Determining the Best Raid Level .................................................................................. 3 Choosing the Number of Drives in a Disk Group ................................................................ 5 Virtual Disk Location and Capacity ............................................................................... 6 Virtual Disk Ownership .............................................................................................. 6 Calculating Optimal Segment and Stripe Size .................................................................. 6 Cache Settings ........................................................................................................ 7 Tuning Using Array Performance Data ........................................................................... 9 Using the Performance Monitor ................................................................................. 13 Other Array Considerations ...................................................................................... 14 Premium Feature Performance .................................................................................. 15 Considering the Host Server(s) .................................................................................. 15 Sharing Bandwidth with Multiple SAS HBAs.................................................................... 15 Considering the System Software ............................................................................... 16 Appendix ............................................................................................................... 18 Appendix A: Obtaining Additional Performance Tools ...................................................... 18 Appendix B: Glossary of Terms .................................................................................. 18

Tables Table 1. Table 2. Table 3.

I/O Size and Optimal Raid Level......................................................................... 4 Storage Array Standard Configuration Specifications ................................................ 9 Performance Tools ....................................................................................... 18

Figures Figure Figure Figure Figure Figure Figure

1. 2. 3. 4. 5. 6.