One of the big changes in mod_balancer between 2.2 and 2.4 is the addition of real dynamic capability, adding and deleting balancers as needed, in addition to changing their runtime config. Because of the former, we need to "pad out" the shm to allow for this growth (you can just add another entry like you can with APR tables, for example). So you can increase, or decrease, that padding w/ the BalancerGrowth config.
The other issue is whether or not balancers are "inherited" by vhosts or not; if balancers are defined in the main server, then depending on your config, they may, or may not, be replicated in the vhosts, and due to how that inheritance happens, you may be wasting space. Unfortunately, the default is the bloated setup, since that was/is backwards compatible :( Hope this helps! > On Feb 26, 2015, at 1:22 AM, Federico Mennite <[email protected]> > wrote: > > Hi, > a few days ago I've submitted the bugreport below > https://bz.apache.org/bugzilla/show_bug.cgi?id=57543 > > I was pondering on removing some rust from my C programming skills and try to > create a patch for this issue. However I'd like to get some feedback from the > developers who worked on it. > > Questions: > - Why weren't such a large number of semaphores and shared memory segments > required for mod_balancer to run in apacche 2.2? > - am I right in stating that the current code in apache 2.4 seems to allocate > a lot more resources than really needed? > - are my behavioral "conclusions" close enough to what the setup code of > mod_balancer is currently doing? > > Thanks for your help, > Federico >
