Hangs !!! Accessing fuse filesystem in Windows through Samba

[Raj Kumar Sanpui]

Hi Richard,

Thanks, as i pointed out in fuse forum as well, moving the blocking call to
read( ) instead of open( ) together with using the AIO interface in Samba
4.1 solved the issue.

However, we noticed the following, after we used the openSUSE Samba 4.1
RPMs on SLES (sles latest official release is 3.6 which has no AIO support):

1) I had mapped 2 CIFS mounts through Linux, and when i tried mapping the
same share in Windows, i got a core dump, which didn't used to happen
earlier.
     Not sure, if the core is really due to dual mapping of Windows + Linux
of same share, which should not be the case.

    Here is the stack trace:

    [2015/03/12 17:57:55.150088,  0]
../lib/util/become_daemon.c:124(daemon_ready)
  STATUS=daemon 'smbd' finished starting up and ready to serve connections
[2015/03/12 18:06:41.292473,  0]
../source3/smbd/smbXsrv_session.c:1353(smbXsrv_session_logoff)
  smbXsrv_session_logoff(0x1a8a958e): failed to delete global key
'1A8A958E': NT_STATUS_NOT_FOUND
[2015/03/12 18:06:41.292563,  0]
../source3/smbd/smbXsrv_session.c:1462(smbXsrv_session_logoff_all)
  smbXsrv_session_logoff_all: count[1] errors[1] first[NT_STATUS_NOT_FOUND]
[2015/03/12 18:06:41.292580,  0]
../source3/smbd/server_exit.c:158(exit_server_common)
  Server exit (termination signal)
[2015/03/12 18:06:41.292596,  0]
../source3/smbd/server_exit.c:161(exit_server_common)
  exit_server_common: smbXsrv_session_logoff_all() failed
(NT_STATUS_NOT_FOUND) - triggering cleanup
[2015/03/12 18:06:41.292765,  0] ../source3/lib/util.c:788(smb_panic_s3)
  PANIC (pid 24942): smbXsrv_session_logoff_all failed
[2015/03/12 18:06:41.293414,  0] ../source3/lib/util.c:899(log_stack_trace)
  BACKTRACE: 21 stack frames:
   #0 /usr/lib64/libsmbconf.so.0(log_stack_trace+0x1a) [0x7f03e35c327a]
   #1 /usr/lib64/libsmbconf.so.0(smb_panic_s3+0x2b) [0x7f03e35c334b]
   #2 /usr/lib64/libsamba-util.so.0(smb_panic+0x3a) [0x7f03e542db7a]
   #3 /usr/lib64/samba/libsmbd-base-samba4.so(+0x16fbbb) [0x7f03e5020bbb]
   #4 /usr/lib64/samba/libsmbd-base-samba4.so(+0x16fe1e) [0x7f03e5020e1e]
   #5 /usr/lib64/samba/libsmbd-shim-samba4.so(exit_server_cleanly+0x12)
[0x7f03e2f82b42]
   #6 /usr/lib64/samba/libsmbd-base-samba4.so(+0x138940) [0x7f03e4fe9940]
   #7 /usr/lib64/libtevent.so.0(tevent_common_check_signal+0x258)
[0x7f03e2021448]
   #8 /usr/lib64/libsmbconf.so.0(run_events_poll+0x23) [0x7f03e35d8fc3]
   #9 /usr/lib64/libsmbconf.so.0(+0x3a5e7) [0x7f03e35d95e7]
   #10 /usr/lib64/libtevent.so.0(_tevent_loop_once+0x9d) [0x7f03e201de4d]
   #11 /usr/lib64/libtevent.so.0(tevent_common_loop_wait+0x1b)
[0x7f03e201deeb]
   #12 /usr/lib64/samba/libsmbd-base-samba4.so(smbd_process+0x7cb)
[0x7f03e4fee5eb]
   #13 /usr/sbin/smbd(+0x8395) [0x7f03e5a8a395]
   #14 /usr/lib64/libsmbconf.so.0(run_events_poll+0x28b) [0x7f03e35d922b]
   #15 /usr/lib64/libsmbconf.so.0(+0x3a68e) [0x7f03e35d968e]
   #16 /usr/lib64/libtevent.so.0(_tevent_loop_once+0x9d) [0x7f03e201de4d]
   #17 /usr/lib64/libtevent.so.0(tevent_common_loop_wait+0x1b)
[0x7f03e201deeb]
   #18 /usr/sbin/smbd(main+0x1422) [0x7f03e5a8bd62]
   #19 /lib64/libc.so.6(__libc_start_main+0xe6) [0x7f03e1cc1c36]
   #20 /usr/sbin/smbd(+0x6879) [0x7f03e5a88879]
[2015/03/12 18:06:41.293539,  0] ../source3/lib/dumpcore.c:318(dump_core)
  dumping core in /var/log/samba/cores/smbd


2) When copying file in Windows from Samba share, we got this error:

"An unexpected error is keeping you from copying the file. If you continue
to receive this error, you can use the error code to search for help with
this problem.
Error 0x80070021: The process cannot access the file because another
process has locked a portion of the file"

However, the above error got resolved when we used: kernel oplocks = no in
smbd.conf

3) Although, it works fine without any issues currently with AIO, but 1 out
of 15 tries, still sometime the Windows Samba share still becomes
unresponsive.
     Is there any way to optimize the performance further?


This is how our smb.conf file looks like:

[global]
       guest account = myinsite
       kernel oplocks = no
       oplocks = no
       msdfs root = yes
       workgroup     = MYINSITE-CIFS
       server string = "MyInSite CIFS Archive"
       security      = user
       map to guest = Bad User
       syslog        = 0

       max smbd processes = 15
       interfaces = eth* lo
       bind interfaces only = no


[DCCAArchive]
        comment = Archive File System
        path = /opt//fuse-mount/ifm
        read only = No
        case sensitive = yes
        public = yes
        writeable = yes
        create mask=0777
        guest ok = Yes
        aio read size = 1
        aio write size = 1


Please suggest.

Thanks in advance.

kingsmasher1


On Tue, Mar 3, 2015 at 8:35 PM, Richard Sharpe <realrichardsharpe at gmail.com>
wrote:

> On Tue, Mar 3, 2015 at 2:44 AM, Raj Kumar Sanpui
> <raj.kumar.sanpui at gmail.com> wrote:
> > Hello Everyone,
> >
> > Thanks for the response.
> > I added these parameters to our smb.conf, and also as Richarde and Miklos
> > (the fuse developer) suggested, moved the blocking part from open( ) to
> > read( ), but with no difference in behaviour, now i am afraid if these
> aio
> > parameters added (as shown below) are really working.
> > I checked the Samba log (log.smbd) in /var/log/samba/, but could not get
> any
> > clue.
> >
> > Is there any way to find out, if the new parameters added for AIO are
> really
> > working?
> >
> > {{{
> > [FUSEAArchive]
> >         comment = Fuse Archive File System
> >         path = /opt/myinsite/fuse-mount/ifm
> >         read only = No
> >         case sensitive = yes
> >         public = yes
> >         writeable = yes
> >         create mask=0777
> >         guest ok = Yes
> >         aio read size = 0
> >         aio write size = 0
> >         aio write behind = /*/
> >
> > }}}
> >
> > Here are my Samba version:
> >       # rpm -qa | grep samba
> >             samba-32bit-3.6.3-0.18.3
> >             yast2-samba-client-2.17.21-0.5.186
> >             yast2-samba-server-2.17.13-0.7.5
> >             samba-client-32bit-3.6.3-0.18.3
> >             samba-3.3.4-0.1.146
> >              samba-client-3.3.4-0.1.146
>
> Whoa, what is it with all these people still running Samba 3.6.3.
>
> That version does not support the aio open parameter.
>
> My next suggestion is that you don't wait for the whole file to
> transfer but start responding to read requests once you have enough
> data.
>
> Either that or shift to a more modern version of Samba, but even there
> there is a limit to how long you can hold off Windows, I believe.
>
> --
> Regards,
> Richard Sharpe
> (何以解憂？唯有杜康。--曹操)
>