SSD Performance HD Tach 3.0.4.0
HD Tach 3.0.4.0
HD Tach is a physical performance hard drive test that uses a special kernel mode VXD to get maximum accuracy by bypassing the file system.
The HD Tach sequential read test is a little bit different from other benchmarks. Most benchmarks create a file on the hard drive and test within that file. The problem is that modern hard drives use a zone bit recording technique that allows different read speeds depending on where the data is located. Data on the outside of the drive is much faster than data recorded on the inside.
Obviously for SSDs this is not an issue. We reach the advertised performance quite well at roughly 210MB/sec measured, for this particular test it's among the fastest we have ever seen for any storage device (not in RAID).
In addition to sequential read performance, HD Tach tests the drive's random access time. Random access is the true measure of seek speed. Many drives advertise sub 10 millisecond seek speeds, but seek speeds are misleading. Also again, without a physical head that needs moving around, the SSDs are just so fast as they have no mechanical moving parts. Here obviously .. the smaller number is better, 0.1 ms (!).
Here's a little test report of HD Tach in both a long READ and WRITE sequence as well. Really fast results, slightly higher than advertised by Corsair, it really shows what the storage unit is capable of, and that definitely is amazing.
But ...
Drive performance degradation
As you guys know, the overall performance of SSD drives tends to become somewhat slower once the drives have been written fully. So the first test we take is actually HD Tach, as you can see from the results above that is stunning performance.
Now after we finished all our tests and the drive has been written a couple of times, this is what performance degradation is resulting in -- still 220 MB/sec reads, yet indeed write performance is somewhat slower now at 176 MB/sec. That remains within advertised speeds and certainly is something acceptable.
It will be interesting to see if Corsair will also introduce a 'garbage cleaning' firmware much like OCZ just announced.
