RE "failing the build of my module" -- the dominant usage is via precompiled binaries we supply. Is there an apr query for determining whether apr was compiled with threads I could do on startup?
-Josh On Wed, Sep 26, 2012 at 7:40 PM, Jeff Trawick <traw...@gmail.com> wrote: > On Wed, Sep 26, 2012 at 7:31 PM, Joshua Marantz <jmara...@google.com> > wrote: > > Looking at source, I see that Jeff's patch, and the 'ttl' parameter in > > general, is only referenced under '#if APR_HAS_THREADS'. When I > > load-tested and found the timeouts, I was testing under Apache 2.2 > Prefork, > > and thus that patched code is not even compiled, IIUC. > > > > However I would still like to know what that parameter is for when > running > > under Worker. > > > > I think the implication of my source journey is also that if my module > > instantiates multiple threads under Prefork (which it does), it must call > > apr_memcache* routines from only one of them. Is that correct? > > APR is usually compiled with thread support even when using the > prefork MPM. Check APR_HAS_THREADS in apr.h. > > If APR_HAS_THREADS is 0 (very unlikely), you probably want to fail the > build of your module to avoid having to worry about this. > > As far as what the parameter means... I'll try to look tomorrow if > nobody replies first. > > See apu_version() for the APR-util version. > > > > > -Josh > > > > > > On Wed, Sep 26, 2012 at 7:17 PM, Joshua Marantz <jmara...@google.com> > wrote: > > > >> +dev (sorry for the duplicate; my first attempt failed due to not being > a > >> subscriber). > >> > >> Keeping modules-dev on CC if that's appropriate. > >> > >> Thanks, Jeff, I was wondering if there was a units issue there. I'm > still > >> wondering if anyone can describe the meaning of that argument in more > >> detail. Is that related to my multiget APR_TIMEUP returns? The phrase > >> "time to live of client connection" confuses me. Would it be > inaccurate to > >> instead say "the maximum number of seconds apr_memcache is willing to > wait > >> for a single operation? Or does it mean *both*, implying that a fresh > >> TCP/IP connection is made for every new operation, but will stay alive > for > >> only a certain number of seconds. > >> > >> I have a practical question about how I release software given this > >> change. Our module (mod_pagespeed) is documented to run with Apache 2.2 > >> and Apache 2.4. It seems like for 2.2 I should probably multiple my > >> desired argument by a million. Same with for 2.4.x and earlier, for > some > >> value of x. How should I work this in my code? Should I query the > version > >> number using an apr utility or something and multiply by a million in > >> certain cases? > >> > >> What's the best practice calling this function for module developers? > >> > >> -Josh > >> > >> > >> On Wed, Sep 26, 2012 at 6:20 PM, Jeff Trawick <traw...@gmail.com> > wrote: > >> > >>> On Wed, Sep 26, 2012 at 5:38 PM, Joshua Marantz <jmara...@google.com> > >>> wrote: > >>> > Hi, > >>> > > >>> > I've been having some success with the apr_memcache_* functions. In > >>> > load-tests, however, I'm finding a lot of timeouts > >>> > with apr_memcache_multgetp. Specifically, the status returned with > the > >>> > individual elements is APR_TIMEUP. > >>> > > >>> > This leads me to wonder what the significance of the second to last > arg > >>> to > >>> > this function is: > >>> > > >>> > apr_memcache_server_create( > >>> > pool_, hosts_[i].c_str(), ports_[i], > >>> > kDefaultServerMin, kDefaultServerSmax, > >>> > thread_limit_, kDefaultServerTtlUs, &server); > >>> > > >>> > I have kDefaultServerSmax initialized to 600, as that's the value I > >>> found > >>> > in mod_socache_memcache.c But that seems stingy (if it's really in > >>> > microseconds). Should I be giving that a few hundred millis instead? > >>> > > >>> > http://apr.apache.org/docs/apr-util/1.4/group___a_p_r___util___m_c.html#ga18ddd72bc1ab5edb0a08a8f26f193bd3 > >>> > claims > >>> > that means "time to live of client connection" but I don't understand > >>> what > >>> > that phrase means exactly, or if it relates to the APR_TIMEUP returns > >>> I've > >>> > been suffering from. > >>> > > >>> > My code is here; > >>> > > >>> > http://code.google.com/p/modpagespeed/source/browse/trunk/src/net/instaweb/apache/apr_mem_cache.cc > >>> > > >>> > -Josh > >>> > >>> d...@apr.apache.org is a better place to ask about details of apr > >>> functions. > >>> > >>> Coincidentally, earlier today I committed someone's fix for the > >>> confusion about the units of ttl: > >>> > >>> http://svn.apache.org/viewvc?view=revision&revision=1390530 > >>> > >>> It is supposed to be in seconds. Pick up the tiny change to > >>> apr_memcache.c and see if that helps anything. You should continue > >>> this discussion on d...@apr.apache.org. > >>> > >>> -- > >>> Born in Roswell... married an alien... > >>> http://emptyhammock.com/ > >>> > >> > >> > > > > -- > Born in Roswell... married an alien... > http://emptyhammock.com/ >
