[Samba] Intermittent slow reads from Samba 2.2.3a server

[Manuel Gomez]

Greetings,

I'm experiencing intermittent speed issues while doing a remote installation
of Win2k from a Samba 2.2.3a server running on Debian Potato.  I experience
similar intermittent slowness while browsing some of the shares as well, so
it's not just file transfers.  We've run a bunch of Win2k installs off of
this server, and sometimes they run very quickly (as I would expect them
to).  

Then, for reasons I don't understand, some of the time it runs really slowly
(I would estimate around 20-30% of the top speed).  At one point, while
checking 'top', I noticed that winbindd was taking a huge amount of memory
(~60 MB, as opposed to ~3 MB); a quick restart of winbindd and the memory
usage dropped back down, but the speed is still exhibiting the same
symptoms.  

My suspicion (ungrounded in any solid evidence) is that winbindd's lookup of
user rights is causing the slow down.  That raises the following question:
could an overloaded WinNT PDC cause winbindd to slow smbd file transfers
down?  Since it's intermittent, I don't believe I have reason to suspect my
NIC or drivers, but I'm open to any suggestions.


Can anyone shed any light on this?


Manuel Gomez
erg at e-r-solutions.com


The following is a clipping of my log.smbd at log level = 3, taken during an
installation of Win2k from a shared folder (during the same period,
/var/log/messages shows no log entries):

[2002/05/07 16:31:58, 3] smbd/process.c:process_smb(860)
  Transaction 8646 of length 86
[2002/05/07 16:31:58, 3] smbd/process.c:switch_message(667)
  switch message SMBopenX (pid 3548)
[2002/05/07 16:31:58, 3] lib/util.c:unix_clean_name(391)
  unix_clean_name [/I386/HANDWE.AN_]
[2002/05/07 16:31:58, 3] smbd/dosmode.c:unix_mode(113)
  unix_mode(I386/HANDWE.AN_) returning 0744
[2002/05/07 16:31:58, 3] lib/util.c:unix_clean_name(391)
  unix_clean_name [I386/HANDWE.AN_]
[2002/05/07 16:31:58, 2] smbd/open.c:open_file(217)
  TRA opened file I386/HANDWE.AN_ read=Yes write=No (numopen=11)
[2002/05/07 16:31:58, 3] smbd/process.c:process_smb(860)
  Transaction 8647 of length 57
[2002/05/07 16:31:58, 3] smbd/process.c:switch_message(667)
  switch message SMBgetatr (pid 3548)
[2002/05/07 16:31:58, 3] lib/util.c:unix_clean_name(391)
  unix_clean_name [/I386/HANDWE.AN_]
[2002/05/07 16:31:58, 3] lib/util.c:unix_clean_name(391)
  unix_clean_name [I386/HANDWE.AN_]
[2002/05/07 16:31:58, 3] smbd/reply.c:reply_getatr(1231)
  getatr name=I386/HANDWE.AN_ mode=32 size=557
[2002/05/07 16:31:58, 3] smbd/process.c:process_smb(860)
  Transaction 8648 of length 55
[2002/05/07 16:31:58, 3] smbd/process.c:switch_message(667)
  switch message SMBreadbraw (pid 3548)
[2002/05/07 16:31:58, 3] smbd/reply.c:reply_readbraw(2228)
  readbraw fnum=11741 start=0 max=4096 min=0 nread=557