|32GB LiteOn Strong-Page MLC SSD LA-32M1S|
|Reviews - Featured Reviews: Storage|
|Written by Olin Coles|
|Saturday, 30 January 2010|
Page 8 of 13
Iometer IOPS Performance
Iometer is an I/O subsystem measurement and characterization tool for single and clustered systems. Iometer does for a computer's I/O subsystem what a dynamometer does for an engine: it measures performance under a controlled load. Iometer was originally developed by the Intel Corporation and formerly known as "Galileo". Intel has discontinued work on Iometer, and has gifted it to the Open Source Development Lab (OSDL).
Iometer is both a workload generator (that is, it performs I/O operations in order to stress the system) and a measurement tool (that is, it examines and records the performance of its I/O operations and their impact on the system). It can be configured to emulate the disk or network I/O load of any program or benchmark, or can be used to generate entirely synthetic I/O loads. It can generate and measure loads on single or multiple (networked) systems.
Benchmark Reviews has resisted publishing Iometer results because there are hundreds of different configuration variables available, making it impossible to reproduce our tests without having our Iometer configuration file. To measure random I/O response time as well as total I/O's per second, Iometer is set to use 4KB file size chunks over a 100% random sequential distribution. The tests are given a 50% read and 50% write distribution. Our charts show the Read and Write IOPS performance as well as I/O response time (measured in ms). Iometer was configured to test for 120 seconds, and after five tests the average is displayed in our benchmark results. The first tests included random read and write IOPS performance, where a higher I/O is preferred.
In the Random IOPS performance tests the single layer cell (SLC) OCZ Agility EX (3982/3988), Intel X25-E Extreme (3543/3548), and OCZ Vertex EX (3106/3091) outperformed all other products by a wide margin. The OCZ Vertex Turbo SSD rendered 1774 read/1770 write I/O's, while the Corsair recorded 1769/1773, both of which are just slightly ahead of a single Vertex SSD that produced 1702 for read and write IOPS. Finishing out the second-tier IOPS performance is the OCZ Agility SSD with 1625/1618. Kingston's SSDNow V+ SNVP325 offered 826/829 IOPS, and creates a third tier of performance. Every other product thereafter responded with low IOPS operational performance, and are not suggested for high input/output applications.
The Iometer random IOPS average response time test results were nearly an inverse order of the IOPS performance results. It's no surprise that SLC drives perform I/O processes far better than their MLC versions, but that gap is slowly closing as controller technology improves the differences and enhances cache buffer space. The Read/Write IOPS performance for the 64GB OCZ Agility-EX SLC SSD was 0.19/0.06 ms, with the Intel X25-E Extreme SSD measuring 0.22/0.06 ms, while the OCZ Vertex-EX achieved 0.26/0.06 ms. Both of these premium MLC products share a dramatic lead ahead of the other SSDs tested.
The Corsair X256 and OCZ Vertex Turbo SSD both scored 0.50/0.06ms, while the Vertex SSD offered 0.52/0.06ms. The mainstream Agility SSD produced 0.55/0.06ms, and the second-generation Kingston SSDNow V+ SNVP325 responded to read requests in 0.27ms while write requests were a bit slower at 0.93ms. The Western Digital VelociRaptor did very well compared against SSD products, producing 6.59/0.82ms. These times were collectively the best available, as each product measured hereafter performed much slower.
In our next section, we test linear read and write bandwidth performance and compare its speed against several other top storage products using EVEREST Disk Benchmark. Benchmark Reviews feels that linear tests are excellent for rating SSDs, however HDDs are put at a disadvantage with these tests whenever capacity is high.