samba - May 2005 - Performance problem when writing large files!

Hello Listmembers!

This is the first time i'm posting to this list. I'm not a native
speaker, so excuse my mistakes.

We're using 

	Redhat with Kernel 2.4.29, 
	12 GB of memory, 
	Dual Itanium Processors
	Scasi Raid controller with filesystem ext3

	Samba V 3.0.14a

We encounter following problem. If somebody on the network writes big files from
windows clients to a samba shared directory, the performance of the server will
be as much degraded, that, using top, on all CPUs 'idle 0.0%' will be
shown and the complete system freezes, up to minutes after stopping the copying
process. After a while the system returns to its normal state, where mostly
ideltimes from 50.0% up to 99.9% are shown. This behavior can be reproduced and
will always happen.

Because for a multi-user environment, such behaviour is unacceptable, I hope,
that somone of the gurus out there can give me a hint, how I can avoid this
problem. Maybe there is an option to tell the Samba-daemon that it shouldn't
use as much system resources or to reduce the allowed write speed, so that other
activities woun't be blocked by Samba.

I'm looking forward to hear from you soon

kind regards.

Josef Fuchs           vox: +43 316 25567 218
Leykam Medien AG      fax: +43 316 25567 69218
Ankerstra?e 4         http://www.leykam.com
A-8057 Graz

Hello Josef,

Tuesday, May 24, 2005, 8:39:27 AM, you wrote:

JFlc> We  encounter  following  problem. If somebody on the network writes
JFlc> big  files  from  windows  clients  to a samba shared directory, the
JFlc> performance of the server will be as much degraded, that, using top,
JFlc> on  all  CPUs  'idle  0.0%'  will  be  shown and the complete
system
JFlc> freezes,  up  to minutes after stopping the copying process. After a
JFlc> while the system returns to its normal state, where mostly ideltimes
JFlc> from  50.0%  up  to 99.9% are shown. This behavior can be reproduced
JFlc> and will always happen.

Maybe  it's  a  HDD controller / driver issue. You should try and set up a
minimal  FTP  server  on the Samba server, and try to upload a big file by
FTP.  If  it hangs, it's not samba. If it works, then maybe it's samba.
In
top,  what's  the  process that uses up the most CPU time, when the system
hangs?


-- 

  Fabio "Kurgan" Muzzi