Re: Extreme slowness with xfs [WAS: Re: Slowness with new pc]

Stian Jordet
2008-11-25T20:44:56Z

ti., 25.11.2008 kl. 01.09 +0100, skrev Sven-Haegar Koch:
> I had the same problem when I tried it on my laptop (T60) - using it on
> the unencrypted root filesystem (with /usr/src) took ages, using it on
> the LUKS encrypted /home was blasing fast - on the same disk.
>
> This test was some time ago with something like 2.6.20 or 2.6.24 - I
> gave up and reformatted / with ext3 as I needed the machine.
>
> I think barriers were the problem, they seem to cost performance like
> hell, especially for operations with many small files. My laptop used
> barriers for xfs on the direct partition, but not on crypto drivermapper
> mounts.
>
> So perhaps try mounting with nobarrier and see if the speed problem goes
> away - but know that you sacrifice some crash-resilience when doing so.

Barriers were the problem indeed. My old system had no problems with
barriers, but here it did an incredible difference.

Thanks!
-Stian