From Fedora Project Wiki
Description
Firefox comes with DTrace probe points that can be used to profile Javascript processes. Want to profile memory, time, etc. on your Javascript, using Fedora 12? This page will show you how.
Requirements
Setup
- Download Firefox source from the above link.
- Create a ~/.mozconfig and fill it as follows (Gently adapted from [| Uxebu])
. $topsrcdir/browser/config/mozconfig mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/obj-ff ac_add_options --enable-debug --disable-optimize ac_add_options --enable-shared --disable-static --enable-dtrace mk_add_options MOZ_MAKE_FLAGS="-s -j4" mk_add_options AUTOCONF="autoconf-2.13"
- Install autoconf 2.13 (
yum install autoconf213) - Enter the mozilla directory and run
make -f client.mk build
Playing
The libmozjs can be found in (source directory)firefox/obj-ff/dist/lib/libmozjs.so, and the binary is located at (source directory)firefox/obj-ff/dist/bin/firefox. To see a list of all available markers, run stap -l 'process("/path/to/libmozjs.so").mark("*")
Example:
Using the following File:Javascript.stp on the 'more complicated example' found here, we get:
File | Function | Time(ms) | Called
--------------------------------------------------------------------------------------
...me/valce/Desktop/draw.html | dot | 0 | 4
...me/valce/Desktop/draw.html | drawBowtie | 1 | 4
...me/valce/Desktop/draw.html | onload | 7 | 1
...me/valce/Desktop/draw.html | draw | 6 | 1