XFS filesystem on Coraid
Just a follow-up on the two previous post I had about the Coraid SAN. Today I formatted a partition as XFS and ran the iozone tests against it. Here are the results:
Coraid w/xfs filesystem, switch and jumbo frames
| Jumbo Frames | Switch Connect |
| /data � xfs write (Kbytes/s) | /data � xfs read (Kbytes/s) |
| 87106 | 97790 |
| 82377 | 98685 |
| 81747 | 96517 |
| 86159 | 98289 |
| 87023 | 98716 |
| 83515 | 98660 |
| 78546 | 98878 |
| 81995 | 97479 |
| 82144 | 99673 |
| 82734 | 98480 |
| 83334.6 (AVG) | 98316.7(AVG) |
Comparing this to previous tests are quite enlightening. First, XFS is the clear leader in the write category. It is over 20MB/sec faster than either ext3 or reiserfs. The read rates are slightly slower than ext3 but it is a very small difference (around 2MB/sec). It is slightly faster than reiserfs.
With the clear write advantage we are very seriously considering using it for our Coraid which will be where we store data for our new cluster.
I have one question. I think I remember that there was a problem with XFS some time ago. If I recall correctly it would actually zero out files with some kind of bug. Another words I might have a very large innodb data file and it ends up as completely empty. Not a good situation. Anyone know about this? If I am correct..has this been resolved?
Thanks for the request to perform this test Stewart. Hope everyone finds it interesting.
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only if programs weren’t doing IO safely. InnoDB does - so that’s safe. Lots of recent efforts also remove the window for applications that don’t do IO safely.
so nothing to worry about.
Awesome. That takes the last nagging doubt out of my head!! Onward with XFS……