[Ocfs2-users] Ftp server... single file seems locked

[Jason Price]

For reference, my 'reader' process that's doing the spinlocking is in
an R state.  The 'writer' process is in a D state, as are every other
proftpd process that's attempting to get to that file.

--Jason

On Fri, Apr 2, 2010 at 3:12 PM, David Johle <djohle at industrialinfo.com> wrote:
>
> FWIW, I have seen a similar problem here on occasion, but with vsftpd
> instead.
>
> When I run `ps -e -o pid,stat,comm,wchan=WIDE-WCHAN-COLUMN` I usually see
> one node with a single vsftpd in D (uninterruptable I/O) state, and multiple
> vsftpd processes on the other node, presumably waiting for the resource.
>
> I also believe this when multiple processes are trying to read & write the
> same file via FTP.  And if left alone for a bit, other programs that may
> read the same file will get hung waiting as well.  Mine are typically not
> busy waits though, but I have seen a couple that were.
>
> Sometimes I will find that all is cleared and back to normal after a short
> while (a timeout somewhere perhaps?).  Usually the only solution is to
> reboot one or both nodes, which I have to instigate via kernel panic/self
> fence because a normal shutdown also gets caught up by the non-killable
> processes.
>
>
> I need to get a netconsole set up to capture some stuff for the next time so
> that I can add it to the bugzilla as well.
>
>
> At 10:52 AM 4/2/2010, Jason Price wrote:
>>
>> Message: 1
>> Date: Fri, 2 Apr 2010 11:38:24 -0400
>> From: Jason Price <japrice at gmail.com>
>> Subject: [Ocfs2-users] Ftp server... single file seems locked
>> To: ocfs2-users at oss.oracle.com
>> Message-ID:
>>        <p2r83f15e31004020838o961f478cg19ae4f403631764 at mail.gmail.com>
>> Content-Type: text/plain; charset="iso-8859-1"
>>
>> I'm setting up an HA ftp server (amongst other services).
>>
>> When two connections happen simultaneously, and (more specifically) the
>> same
>> user from two IP's attempt to access the same file (one for reading, and
>> one
>> for writing), the processes both hang.  And all subsequent attempts to
>> either read or write the file fail.
>>
>> The two processes that seem to have caused the lock:
>> user  24139  1657 Thu Apr  1 18:25:01 2010 proftpd: cbs -
>> ::ffff:xxx.yyy.0.253: RETR prim_wo_img_dom.obs
>> user  24142  1657 Thu Apr  1 18:25:01 2010 proftpd: cbs -
>> ::ffff:xxx.yyy.103.208: STOR prim_wo_img_dom.obs
>>
>> (there are 49 other process trying to do the same things, but these are
>> the
>> first ones.)
>