On 03/04/2009 02:16 PM, Volker Lendecke wrote: > On Wed, Mar 04, 2009 at 01:56:26PM +0100, Alexander 'Leo' Bergolth wrote: >> I'm experiencing strange performance problems after upgrading to samba >> 3.2.8 from 3.0.30. >> >> For all users except smbadmin (who has administrative rights), read >> performance is _very_ bad. Looking at the read-requests using filemon >> and wireshark, I found out that for those users, every read is handled >> transparently (unbuffered) over the net. (I.e. a 2 byte read-request of >> the application leads to a 2 byte Read And X Request over the net.) >> >> If the user is smbadmin, reads are block buffered. (A 2 byte >> read-request of the same application as above leads to a 4096 byte Read >> And X Request over the net.) >> >> Clients are WinXP SP3. >> For details, see my test below.. > > Unfortunately, the log files do not show enough information > about what is happening. Simple tshark output is not > sufficient, see > http://wiki.samba.org/index.php/Capture_Packets for more > information on creating useful sniffs.
OK, here are more details: http://leo.kloburg.at/tmp/samba/abergolth-unbuffered.pcap http://leo.kloburg.at/tmp/samba/smbadmin-buffered.pcap Both files are produced with perl -le "sysopen(F, \"R:/firefox/LICENSE\", O_RDONLY); do { $n= sysread(F, $buf, 2) } while ($n)" Unfortunately I cannot put the server in debug 10 mode now because there are some clients connected... >> When are those buffering parameters negotiated? Do you have any idea why >> the behavior depends on the connected user? > > If it really depends on the connected user, then we need a > debug level 10 log of smbd doing it. I would however suspect > that this depends on the fact if a file is shared between > two users or two applications on the same client box or not. My test case was just reading the firefox LICENSE file, which isn't in use by any other user. I can reproduce this behavior with arbitrary other files. Cheers, --leo -- e-mail ::: Leo.Bergolth (at) wu-wien.ac.at fax ::: +43-1-31336-906050 location ::: IT-Services | Vienna University of Economics | Austria -- To unsubscribe from this list go to the following URL and read the instructions: https://lists.samba.org/mailman/options/samba
