[Mod-security-developers] mod_security mis-uses apr_allocator_create

[Stefan F. <sf...@sf...>]

Hi,

mod_security creates a new apr_allocator for every request which is then 
destroyed again after the request finishes. This seems to cause bad 
performance when used with a threaded mpms and apr's 
--enable-allocator-uses-mmap because it causes lots of mmap() and 
munmap()s for each request. The allocator-uses-mmap option has been in use 
by Debian/Ubuntu's apr packages for over three years. More information is 
available at https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=758068

Why does mod_security do this? Why does it create its own per-request pool 
msr->mp at all? It does not seem to clear or destroy it before the end of 
request and so there does not seem to be any advantage over using r->pool 
directly.

Cheers,
Stefan