HP MSA1500 SAN SCSI Starter Kit

For performance testing we used a pair of Windows Server 2003 systems each equipped with QLogic 2340 2Gbps FC HBAs. Both controllers and servers were connected to the FC switch and we created a six disk RAID-0 stripe on the MSA30. For comparison purposes we also connected an MSA20 enclosure and created another six-disk stripe using 250GB SATA hard disks. One server was assigned to the SCSI volume and the other was assigned to the LUN comprising SATA drives.

We used the open source Iometer utility configured with two disk workers, 64KB transfer requests and 100 per cent sequential reads. Running the test separately on each server showed a small speed benefit for the SCSI drives with Iometer reporting 186MB/sec whilst the SATA enclosure returned 176MB/sec average throughput. The new active-active mode delivered the goods in the speed stakes as running Iometer simultaneously on both servers returned a cumulative read throughput of 371MB/sec. Running the same test with the controllers configured as active-passive only returned a cumulative 189MB/sec.

With read operations the controller's cache plays a larger part in performance than the hard disks so we upped the pressure by reconfiguring Iometer for 100 per cent writes. We also optimised the cache for a 50-50 spread of read and write operations. With one server in the mix we saw Iometer report a very good throughput of 174MB/sec and with it running on two servers we saw a cumulative speed of 213MB/sec.

We're still not overly keen on the mode of management access but HP's SAN starter kit does look comparatively good value. It offers high levels of storage expansion and excellent fault tolerant features and the improvements to the controller specifications and the new active-active mode have made a significant boost to performance.