On Thu, 2006-07-20 at 12:04 -0700, Chris Wedgwood wrote:
> On Thu, Jul 20, 2006 at 12:38:01PM -0400, Ming Zhang wrote:
> > i could not control my application. so i still need to do defrag
> > some time.
> one thing that irks me about fsr is that unless it's given path
> elements it that the files created to replace the fragmented file are
> usually not allocated close the original file (they are openned by
> handle after a bulkstat pass) so you tend to scatter your files about
> if you're not careful
what will be the side effect about this scattering? you want particular
file in particular place?
> also, fsr implies doing a lot more work on the whole, writing, reading
> and rewriting the files in most cases and because it uses dio it will
> invalidate the page-cache of any files that might be being read-from
> when it's running
one thing i worry about fsr is when do fsr and some power loss events
happen, can xfs handle this well?
i will backup before trying these. need some time. ;)
> > yes. i should find out. hope to force a repair?
> umount cleanly and run xfs_repair, check to see how much memory it
> uses with ps/top/whatever as it's running
> > unplug my power cord? ;)
> raid protects against failed disks, it usually doesn't protect well
> against corruption from lost/bad writes as a result of dropping power
> so well, if you have backups, sure, go for it