[Samba] Samba performance/stability issue...

Marcello Melfi
Wed, 14 Jul 2004 01:46:23 -0000

Hi,

I have installed Samba 3.0.2a on a Sun Solaris 8 system using a binary
package (which was compiled with no particlar option) downloaded from the
www.sunfreeware.com web site.

The Samba server is installed and configured with the Domain security level
and has joined a Windows 2003 AD server (in native mode). I have created a
share and a unix logon. The unix logon is associated to that share and is
the same as the windows logon on the client box (which runs Windows XP).
Anyway, even if it was not, I am using the usermaps.txt file to make sure
that no matter the windows logon used, it will be associated to the already
defined unix logon. I know, this may not be very secure for now, but it is
only for testing purposes.

I am performing some benchmarks that will reflect the way I am going to use
Samba. Basically, I am copying/creating, via a simple C++ program running on
the client box, the same 50 K-Bytes file about 10,000 times on the Samba
share. Of course, the file is renamed with a sequence number so that at the
end there are 10,000 newly created files on the share. As you might have
guessed by now, I am not using Samba to simply replace a file server for
windows users. I am using Samba so that a windows application (running in
the background) can export files to another unix applications. NFS could
have been an alternative, but Samba will integrate this export mechanism in
a more transparent fashion.

The problem I have right now is that sometime it takes about 350 sec to
perform that test and a lot more times it takes about 700 sec. Each time, I
am performing the same test without anything different. I noticed that when
it performs faster, the smbd % CPU utilization is 5 to 8% and when it is
slower, the smbd % CPU utilization is about 25 to 35%. When using a windows
share on a windows server instead of Samba on an unix server, it
consistently takes about 485 sec.

Note 1: The network is not on any particular pre-existing load when
performing the test. The same goes for the CPU.

Note 2: Why not using Samba 3.0.4? Simply because there is no binary
available for Solaris 8 and because compiling it is not working for us right
now.

Note 3: Why not using the ADS security level? For the same reason as note 2
: the ADS security level requires compilation with Kerberos and OpenLDAP
development libraries.

Any idea to help resolve this performance/stability issue?

Regards,

Marcello