- Oct 14, 2003
- 8,686
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http://www.mysqlperformanceblo...and-lost-transactions/
"Running this test with default XFS setting I saw SSD was doing 50 writes / s, this is something so forced me to check results several times - come on, it's SSD, we should have much more IO there. Investigations put me into barries/nobarriers parameters and with mounting -o nobarrier I got 5300 writes / s. Nice difference, and this is something we want from SSD.
Now to test durability I do plug off power from SSD card and check how many transactions are really stored - and there is second bumper - I do not see several last N commited transactions.
So now time to turn off write-cache on SSD - all transactions are in place now, but write speed is only 1200 writes / s, which is comparable with RAID 10"
So what he is saying is that the X25-E, will outperform the traditional RAID 10 setup with similar price, but that's with the write cache enabled which due to data loss(they tested it) they won't enable it and the performance will be similar in the end.
That's bad news. This means X25-M is really for average student users and X25-E is for extreme PC users, and there is no server alternative in the SSD world yet. Makes sense though because X25-E is SATA.
"Running this test with default XFS setting I saw SSD was doing 50 writes / s, this is something so forced me to check results several times - come on, it's SSD, we should have much more IO there. Investigations put me into barries/nobarriers parameters and with mounting -o nobarrier I got 5300 writes / s. Nice difference, and this is something we want from SSD.
Now to test durability I do plug off power from SSD card and check how many transactions are really stored - and there is second bumper - I do not see several last N commited transactions.
So now time to turn off write-cache on SSD - all transactions are in place now, but write speed is only 1200 writes / s, which is comparable with RAID 10"
So what he is saying is that the X25-E, will outperform the traditional RAID 10 setup with similar price, but that's with the write cache enabled which due to data loss(they tested it) they won't enable it and the performance will be similar in the end.
That's bad news. This means X25-M is really for average student users and X25-E is for extreme PC users, and there is no server alternative in the SSD world yet. Makes sense though because X25-E is SATA.