jmke

Before looking at performance levels, we ought to look again at what is a fairly specific issue that we have noticed on three of the SSDs, namely a drop in performance in certain cases after being used for the first time.<br>
<br>
With SuperTalent, this came about on both models when we were writing small and medium files to the drive. While write speed for large files was stable at 58 MB/s and 38 MB/s for the DX and MX versions respectively, the situation was quite different for medium-sized files: 28 MB/s and 23 MB/s on first usage but then 19.6 MB/s and 14.7MB/s on the second. For small files we were at 9.9 and 5.4 MB/s first time round and then 6.7 and 3.2 MB/s! We don’t really have an explanation for this, especially as it is something that only happened in this precise case.<br>
<br>
More problematic however is a situation on the Intel drive, also limited to write speeds. As you can see below, the Intel drive does indeed give very impressive performances. Nevertheless, in certain cases, this does suddenly dip. This is particularly, but not only, the case for server load type operations involving random workloads.<br>
<br>
<br>
The “new” drive gives an impressive 37 235 points on PC Mark Vantage for the HDD segment. You can run this test on its own several times and the score remains stable. But, after filling the drive with files of tests used while copying, and this on both partitions meaning virtually 100% of the drive is used, we only get 25 579 points on PC Mark Vantage.<br>
<br>
The same thing happens on a new drive when we run our IOMeter test, itself not particularly stable as you will see below, then PC Mark Vangtage: we get 26 728 points. Even worse, if we redo our file copying test afterwards and then run PC Mark Vantage again, the score drops to 21 427. After multiple combinations we even managed a score of 16 202 points – which is nevertheless 2.5x a VelociRaptor. Repeating this test alone afterwards does give a slightly higher score each time … but without reaching original performance again (22 000 points after 20 repetitions).<br>
<br>
File copying is also affected by multiple usage, even if this test can be carried out on its own several times with the same results. After running PC Mark Vantage and our IOMeter several times and file copying on a new drive, write speeds for large files fall from 70.4 to 43 MB/s, from 47.2 to 12.7 MB/s for medium-sized files and from 20.2 to 7.5 MB/s for small files.<br>
<br>
This drop in performance can even go a good deal further; at one point we measured 6 MB/s for writing large files. This seems to have been an exceptional result that we were not able to reproduce and it should be noted that it is, in any case, only write speeds that are affected in this way.

http://www.behardware.com/art/lire/731/

__________________