Public bug reported:
On Karmic, with 2.6.31-20, I have noticed an important decrease of
performances while navigating CIFS shares (with mount.cifs) on a Windows
2003 server. (Compared to a older installation with 2.6.27-8).
Navigating means here either using midnight commander, ls -l (with ls
unaliased first...), rsync, etc..
The kind of performance degradation I am talking about is in the order
of times ten or so. An rsync which takes less that 2 minutes on old
hardware, now takes over 15 minutes on newer hardware!
Doing a bit of investigation with tcpdump, we can see a lot
QUERY_PATH_INFO requests happening which are not necessary as all the
information is already returned by FIND_FIRST2 requests. A trivial
example will illustrate it. Lets have a directory with 3 files inside.
ls -l with my old machine, it gives:
Protocol Info
SMB Trans2 Request, QUERY_PATH_INFO, Query File All Info, Path: \Temp
SMB Trans2 Response, QUERY_PATH_INFO
SMB Trans2 Request, FIND_FIRST2, Pattern: \Temp\*
SMB Trans2 Response, FIND_FIRST2, Files: . .. file1 file2 file3
With the new one, it gives:
Protocol Info
SMB Trans2 Request, QUERY_PATH_INFO, Query File All Info, Path: \Temp
SMB Trans2 Response, QUERY_PATH_INFO
SMB Trans2 Request, FIND_FIRST2, Pattern: \Temp\*
SMB Trans2 Response, FIND_FIRST2, Files: . .. file1 file2 file3
SMB Trans2 Request, QUERY_PATH_INFO, Query File All Info, Path:\Temp\file1
SMB Trans2 Response, QUERY_PATH_INFO
SMB Trans2 Request, QUERY_PATH_INFO, Query File All Info, Path:\Temp\file2
SMB Trans2 Response, QUERY_PATH_INFO
SMB Trans2 Request, QUERY_PATH_INFO, Query File All Info, Path:\Temp\file3
SMB Trans2 Response, QUERY_PATH_INFO
So for every file in the directory, as returned by the FIRST_FIND2
response, it does a QUERY_PATH_INFO, which does not bring any new
information, all the attributes were already returned by FIRST_FIND2.
Looking around in linux-cifs-client mailing list and contacting a few
developers, it is believed this problem is now fixed in 2.6.31.13, commit
f12f98dba6ea1517cd7fbb912208893b9c014c15. (cifs: fix length calculation for
converted unicode readdir names)
Will 2.6.31.13 make it to Karmic?
Thanks,
Seb.
** Affects: linux (Ubuntu)
Importance: Undecided
Status: New
--
Slow CIFS navigation
https://bugs.launchpad.net/bugs/571235
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
--
ubuntu-bugs mailing list
ubuntu-bugs@lists.ubuntu.com
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
