[linux-cifs-client] can someone please explain the performance difference between mount.cifs and smbclient?

[Volker Lendecke]

On Thu, Jan 27, 2011 at 07:07:19PM +0100, Emmanuel Florac wrote:
> Using mount -t cifs //server/share /mnt/share between two big servers
> connected with 10GigE, I've got : 115 MB/s reading, 132 MB/s writing. 
> Using smbclient, I've got 450 MB/s reading, 132 MB/s writing (NFS gives
> ~ 260 MB/s write, 550 MB/s read on the same setup, with absolutely zero
> optimisation).
> 
> Why this huge difference? BTW, why such a discrepancy between read and
> write speed? 

Good question. There has been a subtle bug in smbclient in
that it did not send out requests as fast as it could (the
events system did not prefer writes over reads). You could
be hitting this bug. But I'd need to analyze this much
closer with an strace -ttT of smbclient and smbd, and a
wireshark trace.

With best regards,

Volker Lendecke

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