[Samba] Samba performance issue

[Aleš Bláha]

Hi Volker,

Thank you for your help. I will try what you propose as soon as I get
to the machines. But, to be honest, I don't think, the hardware is the
bottleneck. The RAID controller and the NIC in the server sit on a
different PCI bus and each one has its interrupt hooked to a
different CPU. Appart from that, as I've mentioned in the previous
post, I can saturate the network when copying files that are cached on
the server - but only as long as there are several pending requests -
with only one I get just those 30MBs or so (one tcp session vs. couple
of them). I will do some more benchmarks next week, post the
smb.conf and tcp/ip stack config.

Regards

Ales


On Fri, 02 Jan 2009 20:48:53 +0100 (CET)
Volker Lendecke <Volker.Lendecke at SerNet.DE> wrote:

> On Fri, Jan 02, 2009 at 05:54:11PM +0100, Aleš Bláha wrote:
> > Both computers run Gentoo Linux 2008, kernel 2.6.25-r9,
> > server runs Samba 3.0.33, client mount.cifs 3.0.30.  The
> > underlying filesystem for Samba is Ext3 with xattr and
> > acls. I wasn't able to break 32MB/s (250Mbps) transfer
> > speed neither reading nor writing to the server. The disk
> > subsystem of the server is capable of 60MB/s and generaly
> > the hardware is not the bottleneck. Neither is the network
> > - the bw_tcp from LMbench suite shows around 108MB/s with
> > 1500b messages, which is what I would expect from GbE &
> > TCP/IP. I've been tinkering with
> 
> In a test I did lately it made a huge difference if I just
> did raw TCP benchmarks, raw disk benchmarks or a combined
> one. The test I used was
> 
> netcat -l -p 9999 > diskfile
> 
> on the receiving end and
> 
> netcat <server-ip> 9999 <diskfile
> 
> on the sending end. This made my hardware which would
> otherwise happily saturate gigE crawl down to something like
> 50MB/sec. Can you try that?
> 
> Volker
> 


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