|Seagate Momentus-XT Solid State Hybrid Drive|
|Reviews - Featured Reviews: Storage|
|Written by Olin Coles|
|Monday, 24 May 2010|
Page 8 of 12
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.
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. While this pattern may not match traditional 'server' or 'workstation' profiles, it illustrates a single point of reference relative to our product field.
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.
SandForce SF-1200 SSDs lead the MLC results, with the ADATA S599 producing 2087/2081 I/O's, Corsair F100 delivers 2077/2076, and the RunCore Pro-V with 2021/2015. Indilinx-based MLC SSDs start with the Corsair Nova delivering 1982/1995, then the OCZ Vertex Turbo SSD rendered 1774/1770, 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 WD SiliconEdge-Blue with 1625/1632 and OCZ Agility SSD with 1625/1618 IOPS.
The SATA 6Gb/s Crucial RealSSD-C300 produced 1070 read-IOPS with 1069 write, and creates a third-level tier of operational performance suitable for personal computer systems. Kingston's SSDNow V+ SNVP325 offered 826/829 IOPS. Every other product thereafter responded with low IOPS operational performance, and are not suggested for high input/output applications or performance-orientated computer systems.
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. Bridging the gap between SLC and MLC construction was the ADATA S599, Corsair F100, RunCore Pro-V (all SandForce SF-1200 SSDs), which produced 0.25/0.25 ms.
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 while Western Digital's SiliconEdge-Blue offered 0.51/0.11ms, the Corsair Nova delivered 0.57/0.09ms, Crucial's 256GB RealSSD C300 responded in 0.87/0.06ms, 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.
Adaptive Memory Technology Notice
The Seagate Momentus-XT Solid State Hybrid Drive employs a proprietary Adaptive Memory technology that improves application performance matching the highest usage patterns. In most cases, benchmark performance tools do not activate the hybrid SSD features of this storage device.
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.