On Wed, Jul 16, 2014 at 7:20 AM, Yann Ylavic <ylavic....@gmail.com> wrote:
> On Wed, Jul 16, 2014 at 12:49 PM, Jeff Trawick <traw...@gmail.com> wrote: > > On Jul 15, 2014 8:46 PM, "Tomlinson, Stuart" <st0...@intl.att.com> > wrote: > >> > >> Are there any expected negative impacts from using "sysvsem" instead of > >> "sem" (which I understand defaults to "posixsem" - described in the > >> documentation as "elegant", whereas "sysvsem" is merely "somewhat > elegant")? > > > > Funny developers... > > > > There is safety in numbers (i.e., use what other people on your platform > > use, unless you have a specific problem). sysvsem is the default on > Linux. > > (I assume you are using Linux, but maybe that is not the case.) > > > > Using sysvsem on Solaris with the prefork MPM, you would likely have to > > increase the number of semaphore undo structures (at least in the old > days; > > I can't find my normal go-to reference for AcceptMutex oddities; Eric?) > > SSLMutex/AcceptMutex "pthread" work very well on Linux, and have the > advantage to be "robust" against children crashing while holding the > lock (like sysvsem, unlike posixsem AFAICT), without system limits > (unlike sysvsem). > > This is probably true for all unixes that HAVE_PTHREAD_MUTEX_ROBUST > (ie. pthread_mutexattr_setrobust_np), but I can't verify that. > > Regards, > Yann. > > I won't disagree with you at all Yann, but in the interest of promoting the idea that you don't actually have to use all the configuration httpd offers: If the poster had not made a change from the default based on some developer's silly comment in the documentation, they wouldn't have encountered a problem. It is best to leave the mutex type alone unless you have a specific issue. -- Born in Roswell... married an alien... http://emptyhammock.com/
