Samba speed

[Jeremy Allison]

On Mon, Dec 08, 2008 at 05:39:24PM -0500, Theodore Tso wrote:
> On Mon, Dec 08, 2008 at 10:21:14AM -0800, Jeremy Allison wrote:
> > Here's a really interesting paper from Intel
> > that they recently brought to my attention.
> > 
> > http://software.intel.com/en-us/articles/windows-client-cifs-behavior-can-slow-linux-nas-performance
> > 
> > Looks like using XFS for your Linux Samba
> > server, or setting "strict allocate = yes" can make
> > a big difference due to sparse file issues.
> 
> Glibc 2.7 (as shipped in Ubuntu Hardy) has posix_fallocate wired up to
> the fallocate system call, and ext4 supports delayed allocation as
> well as preallocation.  There are number of userspace applications ---
> rsync, samba, and most bittorrent applications come to mind --- where
> use of fallocate would be a big win.

Turns out that ext4 doesn't suffer from the slowdown in the
first place. The paper is extremly interesting, I'm looking
at the implications for our default settings (most users
are still using Samba on ext3 on Linux).

Jeremy.