Version and / or Patch Used: 1.1.0
Product Homepage: http://www.iometer.org
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's become wide spread within the storage industry.
We use Iometer to measure disk response times. Disk response times are measured at an industry accepted standard of 4K QD1 for both write and read. Each test is run twice for 30 seconds consecutively, with a 5 second ramp-up before each test. The drive/array is partitioned and attached as a secondary device for this testing.
Average Disk Response
Write response times benefit most from RAID 0 because of write caching. There is a slight latency increase in read response times for an array vs. a single drive. Our array displays excellent write response and average read response times.
Maximum Disk Response
Maximum disk response times are difficult to nail down because they can vary so much from one run to the next, even when running the same drive.
We chart them anyway, because while they may vary from one run to the next, the chart gives us a pretty good overall picture of what to expect from our particular test subject. Low maximum latency is a valuable attribute of LAMD controllers. Low maximum latency is a key ingredient to consistent long term performance and our Seagate 600 array outperforms the rest of the arrays on our chart in this metric.