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TECHNICAL REPORT: Performance Study Protecting Microsoft SQL Server databases with Equal Logic Synchronous Replication ABSTRACT Equal Logic Sync Rep allows users to protect their Microsoft SQL Server ...
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Copyright © 2012 Dell Inc. All Rights Reserved. Equal Logic is a registered trademark of Dell Inc. Dell is a trademark of Dell Inc. All trademarks and registered trademarks mentioned herein are the pr...
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Preface Equal Logic PS Series arrays are easy to use and they optimize resources and simplify operations by automating many performance enhancement and network load balancing tasks. Additionally, PS S...
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TABLE OF CONTENTS Revision Information........................................................................................................ iii Executive Summary.......................................
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REVISION INFORMATION The following table describes the release history of this Technical Report. Report Date Document Revision 1.0 October 2012 Initial Release The following table shows the software a...
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EXECUTIVE SUMMARY Online Transaction Processing (OLTP) applications are by far some of the most mission critical applications in an enterprise. Protecting an organization’s OLTP application data and m...
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both the active and alternate volumes is hardened in the protected cache of the PS series members. If one pool is not available due to a power failure or other resource outage, volume data from the ot...
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SYNCREP TERMINOLOGY AND STATES Sync Rep feature is enabled on a per-volume basis. For Sync Rep-enabled volumes, the volume data exists simultaneously in two different pools. Snapshots will exist in wh...
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TEST CONFIGURATION AND TOOLS In order to test a typical synchronous replication scenario in a campus environment a set of volumes containing a SQL Server 2008 database was configured with Sync Rep fro...
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Test goals: A. Simulate a TPC-C style database transactional workload while gathering application transactions per second (TPS) and end-to-end transaction response time data under increasing user load...
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SQL SERVER Microsoft SQL Server 2008 SP1, 64-bit, provided the database services for the TPC-C clients. The SQL Server was hosted on a Dell Power Edge R610 server with dual-socket hex-core Intel Xeon ...
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Figure 2: Equal Logic test system configuration for a synchronously replicated campus site Note: This environment was setup just for the test lab purposes. Please refer to the Reference Architectures ...
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this group. Each database was assigned eight volumes. Of the eight volumes, six were data volumes, one was a log volume, and one was a tempdb volume. All eight volumes for a single database were part ...
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The following three scenarios were tested using this configuration: A. For scenario A, a TPC-C style database transactional workload was generated while gathering transaction per second (TPS) and end-...
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which was in a different storage pool but within the same PS Series group. (Scenario A). Figure 3: Application TPS and Average transaction response time for a single member pool In Figure 3, the dotte...
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Sync Rep test run doubled from that of the test run without Sync Rep enabled. This is due to the fact that with Sync Rep enabled, the writes that are written to the volume in Sync Active pool are simu...
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independent copies of the same data. Since the write IOPs double, this will result in increasing the write latency on the storage system. The configuration parameters for these tests are shown in Tabl...
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Figure 6: Read IOPs stay constant while write IOPs double with Sync Rep on single array as well on a three array configuration. Figure 7: Application TPS with and without Sync Rep feature enabled
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Once again, as mentioned in the text box on Page 5, the best way to interpret the results in Figures 6 and 7 is not to focus on the absolute TPS results achieved, but to focus on the percent differenc...
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Switchover A pool switch for a Sync Rep volume swaps the roles of the Sync Active and Sync Alternate pools. As part of the operation, the Sync Active pool becomes the Sync Alternate pool and the Sync ...
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Figure 9: Switchover warning message The switch was performed with four Quest Benchmark Factory instances running a TPC-C OLTP workload against four SQL databases and completed almost instantaneously ...
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Pool2 Pool1 (Sync Active) (Sync Alternate) Figure 11: PS Series Group Manager GUI after switchover completes Table 4 summarizes the test results that were captured during the switchover tests: End-Use...
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Average IOPS Average IOPS Reads: 1,118 Reads: 1,242 Writes: 3,990 Writes: 3,984 Average Latency Average Latency Reads: 8.10 ms Reads: 10.65 ms Writes: 6.25 ms Writes: 8 ms Figure 12: SANHQ metrics for...
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Figure 14: i SCSI Initiator and MSSQL Server Management Studio after failover CONCLUSION Many OLTP applications in real production environments also exhibit characteristics similar to the TPC-C benchm...
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Technical Support and Customer Service Dell support service is available to answer your questions about PS Series SAN arrays. Contacting Dell 1. If you have an Express Service Code, have it ready. The...
