I use Solaris zones a lot.
We've got a number of X2200s, in two variants. Some just run web front ends, and are fitted with SATA drives (once running, the only disk activity is the web server logs); the database back-ends have SAS drives.
OK, so the SAS drives are expected to be a bit quicker - we did get them for that purpose. Based solely on the rotational speed, there's about a factor of 2 difference in performance.
However, if you take zone creation time as a metric, the performance difference is rather larger than a factor of 4. Something else makes the SAS drives fly and the SATA drives crawl.
2 comments:
I've noticed this too.
The seek times are much better on SAS drives (especially 2.5" SAS drives) than SATA drives, so isn't that going to be more of a factor than rotational speed? Of course, the rotational speed helps to make the seeks faster, but raw data transfer isn't going to have much effect for zone creation.
My shot: TCQ on SAS drives and lack of NCQ on SATA ones.
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