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IOMeter — Sequential and random performance
IOMeter fuels much of our latest storage test suite, including our sequential and random I/O tests. These tests are run across the full capacity of the drive at two queue depths. The QD1 tests simulate a single thread, while the QD4 results emulate a more demanding desktop workload. For perspective, 87% of the requests in our old DriveBench 2.0 trace of real-world desktop activity have a queue depth of four or less. Clicking the buttons below the graphs switches between results charted at the different queue depths.

Our sequential tests use a relatively large 128KB block size.



The SP550's sequential reads speeds are impressive. At both queue depths, it reads as fast as anything else we've got (except for our crowd of PCIe drives, of course). Unfortunately, the drive's sequential writes are lackluster. To its slight credit, it manages to edge out our record-holder for the worst sequential write performance, Crucial's BX200. But that's a hollow victory when you consider that even the decrepit Intel X25-M writes faster. Hopefully the SP550's random performance will prove stronger—otherwise, I fear for the drive's place in our overall performance index.



Thankfully, the SP550 turns out to deliver reasonable random numbers. Random reads are a bit pokey, but random writes at both queue depths are more than acceptable. The SP550 punches far above its weight class here, beating some much more expensive drives.