HP LeftHand P4000 HP LeftHand SAN Solutions Support Document - Application Not - Page 9

and database average read latency should be less than 20ms. LeftHand Networks uses an automated command line version of Jetstress that will increase threads until the test no longer passes and records the IOPS of the last passing run. The highest IOPS achieved while still passing is the value reported in this paper. Best Practice - Keep the email database files and log files on separate volumes. File Copy Using Robust File Copy The file copy test is a straight-forward Windows file copy. Using robocopy.exe a file copy of one hundred 100MB files is done from direct attached storage (DAS) in the server to a volume on the SAN. For this test a simple measurement of megabytes per second is taken. Robocopy (Robust File Copy) is included in the Windows resource kit. While individual file copy speeds are limited by the nature of low queue depth disk operations, the architecture of a LeftHand Networks SAN solution is capable of handling multiple file copy jobs simultaneously without degrading performance. This is represented by the "Concurrent Jobs" set of data. Best Practice - When copying from DAS to the iSCSI SAN remember the file copy cannot go any faster than the DAS disk. Make sure the disk that the source files are on is the fastest disk available to you otherwise it might be limiting the file copy speed. Running multiple file copies at a time will increase the aggregate performance. IOmeter IOmeter is an I/O subsystem measurement and characterization tool. IOmeter is a good tool for simulating loads of different I/O sizes to demonstrate a system's IOPS and throughput capabilities. These configurations are designed to show typical speeds as opposed to the maximum values. Best Practices - Run IOmeter against raw disks to avoid file system cache interference. 9