Re: Race Condition In PHP Session Handler

On Mon, 2012-02-20 at 20:02 +0100, Matijn Woudt wrote: > On Mon, Feb 20, 2012 at 7:21 PM, Adam Tauno Williams > <awilliam@whitemice.org> wrote: > > php-5.3.3-3.el6_2.6.x86_64 > > 2.6.32-220.4.2.el6.x86_64 > > The PHP session file. Originally I had a tmpfs mounted for the session > > files. I removed that and used the underlying filesystem. Same issue. > > I disabled APC. Same issue. > > Switching the the memcache session handler resolved the issue, although > > that may be less optimal. But this seems like a PHP bug. > > Backtrace of a hung httpd - > > #0 0x00007fa175af9be7 in flock () from /lib64/libc.so.6 > > #1 0x00007fa16cb59dfc in ?? () from /etc/httpd/modules/libphp5.so > > #2 0x00007fa16cb5a047 in ?? () from /etc/httpd/modules/libphp5.so > > #3 0x00007fa16cb56e4c in php_session_start () > > from /etc/httpd/modules/libphp5.so > > #4 0x00007fa16cb57559 in ?? () from /etc/httpd/modules/libphp5.so > > #5 0x00007fa16cc9afe8 in ?? () from /etc/httpd/modules/libphp5.so > > #6 0x00007fa16cc72320 in execute () from /etc/httpd/modules/libphp5.so > It sounds like a bug in memcache to me, but anyway, there's little No, switching *to* memcache as the session handler worked around the issue. > chance you're getting any info from this mailing list. Expected; just thought I might get lucky with somone who was using the same current packages. > You should opena bug report at bugs.php.net for this. If you want to be even more > helpful, provide a backtrace with debug symbols included. I'm working on getting a full stack trace, but the CentOS debuginfo packages are lagging behind. -- System & Network Administrator [ LPI & NCLA ] <http://www.whitemiceconsulting.com> OpenGroupware Developer <http://www.opengroupware.us> Adam Tauno Williams