> My main problem is: Memory Usage.
> Currently, the apache processes take (each) about 150 MB memory, > what's quite a lot. Now, i've been wondering which module and why it > takes that much memory at all.
Check out this thread: http://aspn.activestate.com/ASPN/Mail/Message/modperl/3173671
> My understanding (perl memory handling, garbage collection) is, that > objects are destroyed as soon as functions are finished. How about > this in mod_perl? It seems as if a lot of unnecessary things are > cached. I can't just measure how much memory is used and restart the > processes using several modules, since that would definitely result in > a runtime performance problem.
perl garbage collects when the variable goes out of scope, but it doesn't return the memory to the system. See http://perldoc.perl.org/perlfaq3.html#How-can-I-free-an-array-or-hash-so-my-program-shrinks%3f
in simple terms: mod_perl destroys the objects, but it holds onto the memory for the lifetime of the child. if a single var ups your child's memory by 5mb, that 5mb will stay reserved for the child until it dies.
This is correct. I've argued that this is a good thing: http://foobarbazbax.livejournal.com/4953.html
> Do you have any advice, how to measure functions and / data which is > kept? Or generally what takes that much memory? I definitely don't > need to keep this data, since it would always change (per-request).
See Apache::LogMemoryUsage, which isn't on CPAN, but I pasted in that same thread I referenced above: http://aspn.activestate.com/ASPN/Mail/Message/modperl/3175357 Best of Luck, Jay
