398241 - mod_perl isn't using our precompiled CGIs

Status: RESOLVED FIXED

(Bugzilla :: Bugzilla-General, defect)

Description

[Max Kanat-Alexander]

I was messing around with our mod_perl installation on landfill, and the perl-status page on landfill that shows information about the system.

I found something curious:

It listed some pages as having been compiled for "ModPerl::Registry" and some pages as having been compiled for "Bugzilla::ModPerl::ResponseHandler".

It turns out that since we have a custom handler, mod_perl isn't using our precompiled pages at all. They're just taking up memory and not improving performance. When I fixed the landfill mod_perl install to actually use the precompiled pages, there was a huge performance increase. This should also help a lot with the fact that our processes grow huge slowly over time. (We're compiling every page twice.)

Comment 1

[Max Kanat-Alexander]

Note this also means that every single Apache process was compiling its own scripts, instead of just compiling them once and sharing them between all the children.

Comment 2

[Max Kanat-Alexander]

Attachment: v1

This fixes it, as tested and now running on landfill.

Comment 3

[Frédéric Buclin]

Comment on attachment 283144 [details] [diff] [review]
v1

I know nothing about mod_perl. I will let justdave review it.

Comment 4

[Yann]

Does that mean you will be able to remove the use of Size::Limit module that prevents the use of mod_perl on windows ?

Comment 5

[Max Kanat-Alexander]

(In reply to comment #4)
> Does that mean you will be able to remove the use of Size::Limit module that
> prevents the use of mod_perl on windows ?

  No. You could remove that now, if you want, as long as you feel OK that Apache may consume all of your memory at any particular moment.

Comment 6

[Dave Miller [:justdave]]

Comment on attachment 283144 [details] [diff] [review]
v1

Serious speed improvement on a freshly-restarted apache.  It also appears to drop memory consumption by about 10M per-process, presumably because we no longer have two copies of everything loaded after it's been running for a bit.  Two thumbs up! :)

Comment 7

[Dave Miller [:justdave]]

previous test was on 3.0 branch, just tested on the tip and works great there, too. :)

Comment 8

[Max Kanat-Alexander]

This was our biggest 3.0.3 blocker. I think we should release 3.0.3 as soon as possible, now. Unfortunately, with LpSolit gone for December, that might be hard. Perhaps somebody else could run QA on 3.0?

tip:

Checking in mod_perl.pl;
/cvsroot/mozilla/webtools/bugzilla/mod_perl.pl,v  <--  mod_perl.pl
new revision: 1.7; previous revision: 1.6
done

3.0 branch:

Checking in mod_perl.pl;
/cvsroot/mozilla/webtools/bugzilla/mod_perl.pl,v  <--  mod_perl.pl
new revision: 1.5.2.1; previous revision: 1.5
done

Comment 9

[Max Kanat-Alexander]

Relnoted in 3.0.3 when it was released.