samba - Jun 2007 - Performance tweaking for lots of files

Hullo,

I'm looking for performance-tweaking of our samba server (linux, 
RHES4-based). Looking around on the internet I found plenty of things 
that stated 'the usual' things (buffer-sizes, nodelay, logging to a 
minimum, etc), but nothing that actually seems to work. We usually have 
directory structures with many thousands (up to 100k or more) of 
relatively small files (around 10MB each) and whatever I try, it goes 
pretty damn slow. I'm getting about 1 file every second, which comes 
down to somewhere between 50 and 100Mbit (and we've got a gigabit network).

The files are on a StorNext filesystem that usually has no problem 
delivering 300MB/sec or more, so that shouldn't be a problem. Netperf 
also has no problems filling the lines, so that works as well.

Anybody have any suggestions on getting things faster, or at least to 
check what's going wrong?

Kind regards,
  Jeroen

-- 
Jeroen Akershoek - Systems Engineer
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tel: +31 20 5309696   fax: +31 20 5309697

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On Fri, Jun 01, 2007 at 04:10:03PM +0200, Jeroen Akershoek
wrote:
> Hullo,
> 
> I'm looking for performance-tweaking of our samba server (linux, 
> RHES4-based). Looking around on the internet I found plenty of things 
> that stated 'the usual' things (buffer-sizes, nodelay, logging to a
> minimum, etc), but nothing that actually seems to work. We usually have 
> directory structures with many thousands (up to 100k or more) of 
> relatively small files (around 10MB each) and whatever I try, it goes 
> pretty damn slow. I'm getting about 1 file every second, which comes 
> down to somewhere between 50 and 100Mbit (and we've got a gigabit
network).
> 
> The files are on a StorNext filesystem that usually has no problem 
> delivering 300MB/sec or more, so that shouldn't be a problem. Netperf 
> also has no problems filling the lines, so that works as well.
> 
> Anybody have any suggestions on getting things faster, or at least to 
> check what's going wrong?
You're running into the classic "too many files per directory"
problem with emulating case insensitivity on a POSIX filesystem.

See this post for details on fixing it :

http://lists.samba.org/archive/samba-technical/2005-February/039408.html

It's in the main codebase now, so should apply to your situation.

Jeremy.

On Thu, Jun 07, 2007 at 11:41:07AM +0200, Jeroen Akershoek
wrote:
> 
> First, this assumes all the same case (upper or lower), which isn't, 
> well, the case.
So that's what you've got to fix to make it go fast.

Jeremy.