[Samba] SMB hogs cpu - printing freezes server

Craig Silva csilva at moreland.vic.gov.au
Fri Jun 13 02:35:28 GMT 2003

We have 2.2.7a running on redhat 9.0  with 256 MB ram. Dual cpus - but
only PII 300's.  Its not running as a PDC - the PDC is an nt box.

The system is set up as our main print server with 60 odd print queues
that service a wide variety of printers. Approx 200 odd windows pc's as
clients. The print files themselves can be largish with multi-page docs
with lots of graphics.

What we are finding is that under certain circumstances (which appears
to be a number of big print jobs hitting the server and or users
browsing their printers) the smbd processes clog up the cpu - we were
running top and vmstat to try to get a handle on what happens when it
freezes. These processes start to take an increasing percentage of both
cpu and memory with the root owned smbd process topping out at a
reported 99% the last time the system froze. These processes hang about
in top - they don't drop out as is the case when the system is running

We are runing individual logs for each machine and get various error
messages in them with the main appearing to be
/var/cache/samba/printing.tdb): rec_read bad magic .....

The main log consistently reports the following error message: 

Failed to setup RT_SIGNAL_LEASE handler

We are using lprng as we thought it was CUPS creating the problem and
since using lprng we are also getting a symptom that on the windows 2000
client, when looking at the print queue, the last job printed remains in
the window until aother job pushes it out.

The questions I have are whether the system is not sufficient to handle
this task. Do we need to split the number of printers over a couple of
is there a memory leak. I sthere a way that we can throttle smbd so
that it can cope with peaky printing demand.

Final question - should I stick with samba mailing list or run this in

of course thanks for any help in advance.

Craig Silva, IT Infrastructure Coordinator
Moreland City Council, 90 Bell St. Coburg.
Melbourne. Victoria. 3058. Australia.
email: csilva at moreland.vic.gov.au 
Tel: +61 3 9 240 2355, fax: + 61 3 9 240 1212
For Fun: - http://www.sysadminday.com/

More information about the samba mailing list