Bug 343166: $template->process leaks 512K of RAM per call under mod_perl

Bugzilla.pm

@@ -300,7 +300,21 @@ sub custom_field_names {
 sub request_cache {
     if ($ENV{MOD_PERL}) {
         require Apache2::RequestUtil;
-        return Apache2::RequestUtil->request->pnotes();
+        my $request = Apache2::RequestUtil->request;
+        my $cache = $request->pnotes();
+        # Sometimes mod_perl doesn't properly call DESTROY on all
+        # the objects in pnotes(), so we register a cleanup handler
+        # to make sure that this happens.
+        if (!$cache->{cleanup_registered}) {
+             $request->push_handlers(PerlCleanupHandler => sub {
+                 my $r = shift;
+                 foreach my $key (keys %{$r->pnotes}) {
+                     delete $r->pnotes->{$key};
+                 }
+             });
+             $cache->{cleanup_registered} = 1;
+        }
+        return $cache;
     }
     return $_request_cache;
 }