IOMeter v2006.07.27 – IOps
Iometer is an I/O subsystem measurement and characterization tool for single and clustered systems. It was originally developed by the Intel Corporation and announced at the Intel Developers Forum (IDF) on February 17, 1998 – since then it got wide spread within the industry.
Meanwhile Intel has discontinued to work on Iometer and it was given to the Open Source Development Lab (OSDL). In November 2001, a project was registered at SourceForge.net and an initial drop was provided. Since the relaunch in February 2003, the project is driven by an international group of individuals who are continuesly improving, porting and extend the product.
Light desktop usage sees QD figures between 1 and 4. Heavy / power user loads run at 8 and higher. Most SSD's are not capable of effectively handling anything higher than QD=32, which explains the plateaus.
Regarding why we use this test as opposed to single-tasker tests like 4KB random reads or 4KB random writes, well, computers are just not single taskers. Writes take place at the same time as reads. We call this mixed-mode testing, and while a given SSD comes with side-of-box specs that boast what it can do while being a uni-tasker, the tests above tend to paint a very different picture.
The results here are a bit of a mixed bag. For lower QD, we see many other drives surpassing the 520 and 335. With a longer data pipeline with more stages to pass through, SandForce has always shown a weakness at lower Queue Depths. The 335 and 520 are both surpassed by the Samsung 830, 840, OCZ's Vertex 4, and even Intel's own 320 Series (a SATA 3Gb/sec drive). With higher Queue Depths, however, the 335 picks up some steam, but again, this SandForce controller is a bit long in the tooth, and other controllers are capable of lower latencies and higher IOPS. Still, not bad at all for what is likely to be a budget consumer SSD.