[CentOS] Fwd: Bug 800181: NFSv4 on RHEL 6.3 over six times slower than 5.8

Wed Jul 11 16:49:29 UTC 2012
Les Mikesell <lesmikesell at gmail.com>

On Wed, Jul 11, 2012 at 11:29 AM, Colin Simpson
<Colin.Simpson at iongeo.com> wrote:
>
> But think yourself lucky, BTRFS on Fedora 16 was much worse. This was
> the time it took me to untar a vlc tarball.
>
> F16 to RHEL5 - 0m 28.170s
> F16 to F16 ext4 -  4m 12.450s
> F16 to F16 btrfs - 14m 31.252s
>
> A quick test seems to say this is better in F17 (3m7.240s on BTRFS but
> still looks like we are hitting NFSv4 issues for this but btrfs itself
> is better).

I wonder if the real issue is that NFSv4 waits for a directory change
to sync to disk but linux wants to flush the whole disk cache before
saying the sync is complete.

-- 
  Les Mikesell
     lesmikesell at gmail.com