Firefox performance

[Gregory Maxwell]

On Sat, Feb 14, 2009 at 2:45 PM, drago01 <drago01 at gmail.com> wrote:
> On Fri, Feb 13, 2009 at 5:45 PM, Adam Pribyl <pribyl at lowlevel.cz> wrote:
>> Is there anything we can do to improve the Fedora picture?
>> http://www.tuxradar.com/content/browser-benchmarks-2-even-wine-beats-linux-firefox
>>
>> Adam Pribyl
>
> The windows firefox build is compilied with PGO (profile guided
> optimization) which should improve JS perfomance by ~11%, see
> http://gemal.dk/blog/2008/03/04/firefox_3_with_profileguided_optimization_speeding_ticket/

You can -fprofile-use  with GCC, but it makes the build process
tricky— especially with an X11 app. (A pure batch processing CLI app
could easily have a scripted profile generation process).

In my own (limited) experience 11% would be well on the high end of
what you can get from GCC's profile driven optimizations, but clearly
the benefits can be considerable and it can also result in smaller
binaries (avoiding unprofitable inlining).

Especially since FF 3.1 has a rewritten JS engine, the bigger question
is "Should more of Fedora be built using profile driven
optimizations?".  Considering that you're looking at tripping the
build time and making compilation less deterministic, I don't know if
thats an easy decision.