Apache memory growth for RT

I’m pretty confused.

We have an Apache-served RT 3.8.7 instance with Postgres
backend. It’s using mod_perl. All 10 current httpd
processes are over 300MB each already after a host
reboot 30 hours ago.

We have a NON-RT system, with the same OS and package
versions, serving 10 times more people via mod_php +
Postgres (a SourceForge-like system). All current
httpd processes are ~50MB after being up for 5 days.

What gives? Any ideas?

I’m pretty confused.

We have an Apache-served RT 3.8.7 instance with Postgres
backend. It’s using mod_perl. All 10 current httpd
processes are over 300MB each already after a host
reboot 30 hours ago.

We have a NON-RT system, with the same OS and package
versions, serving 10 times more people via mod_php +
Postgres (a SourceForge-like system). All current
httpd processes are ~50MB after being up for 5 days.

What gives? Any ideas?

The memory footprint depends completely on the coding
and resource needs of the software. RT caches a lot of
data to improve performance. There are also some code
areas that cause bad memory bloat if used. There is one
issue with reading in the meta-data for every ticket
found in a search when you select one of the search
result tickets for display. The effect scales with the
size of the result set. We have blown out our VM
footprint to almost 2GB per httpd process and needed
to restart httpd to regain memory and reasonable
performance. I think that problem was fixed in 3.8.9
or 10 which is why we are eager to upgrade. Other than
that our starting VIRT footprint for Apache/mod_perl
is just over 300MB.

Cheers,
Ken