This is known issue and it does not matter if system is SMP or not. Multiple users have been reporting this problem on occasion.
-- Yasuo Ohgaki Warwick Poole wrote: > I dont know if this is the correct forum to ask this question, but I > have spent a good day trying to find the answer to this with no real > success, so I thought I would try the source...the PHP developers. > > I am building a cluster of 3 webservers, which are going to serve a > group of PHP (with some Perl scripts as well) websites. Its a high load > environment so I have gone with SMP machines (dual Processor i686, 1GB > RAM, running a tuned RedHat 7.2 with kernel 2.4.18 with tweaks). > > I am trying to tweak the OS, Apache and PHP as far as I possibly can. I > want to use Shared Memory for the session handlers in PHP, so I have > compiled with --with-mm and set "session.save_handler=mm" in php.ini. > > I have been told that PHP has "serious concurrency bugs" when using SMP > machines and shared memory. I cant find this documented anywhere. > However I am told that the current-stable 4.1.2 still has issues with > SMP and SHM whereas the CVS version (which built as 4.2.1-dev on my > machine) has resolved this issue. > > What is the current status regarding this? Any information that you can > share would be greatly appreciated. > > Thanks > Warwick Poole -- PHP Development Mailing List <http://www.php.net/> To unsubscribe, visit: http://www.php.net/unsub.php
