Clone this wiki locally
This is being superseded by DMD, see bug 1014346
Refgraph, a mozilla-central fork to study the graph of references between heap objects
Known to work:
- Desktop Linux 64bit
Should work, untested:
- Desktop Linux 32bit
Not yet supported (pull requests welcome, should not be hard):
Building and running
- Check out this Git repository:
git clone email@example.com:bjacob/mozilla-central.git mozilla-refgraph cd mozilla-refgraph
- Switch to the refgraph branch:
git checkout refgraph
Build as usual. This fork takes care of enabling the configure options it needs in
configure.in, which are
--enable-cpp-rtti. No need for
--disable-optimize. We don't currently do any stack walking.
You should now have two things: an instrumented build of your browser, and a librefgraph.so there:
The two cannot be used without each other.
- To run your browser, just preload librefgraph, like this:
- This browser has a special
about:refgraphpage that has the user interface to refgraph. Navigate to it, click on "Take a snapshot of this browser" and then on "Cycles summary". More detailed usage instructions below.
If you have a build failure, that's not surprising for such a new/immature tool; pull requests welcome.
If the browser fails to run or crashes on startup, the most likely cause would be failure to preload the library. Try setting LD_PRELOAD to an absolute path; verify that librefgraph is preloaded (using e.g.
/proc/$PID/maps). Or let me know.
Follow above steps 1. and 2. to get a clone of this repository and switch to the refgraph branch.
Point your B2G build environment to it instead of its default gecko tree. One possibility is to add it as a remote in your gecko tree, pull it, and switch to the refgraph branch there. Or you could follow these instructions.
Patch your gonk-misc tree with gecko/b2g/refgraph-gonk-misc.patch
Build and flash as usual
At any time, you can save refgraph snapshots of all B2G processes by running
Notes: **1:**Yes, we currently hijack jlebar's get_about_memory tool to do something different. This is temporary. It will save the snapshots in /data/local/tmp/refgraph-$PID . 2: This hicjacked get_about_memory.py script will stall. Just hit Ctrl-C immediately. 3. Patches very welcome to get our own proper script.
- Pull these files from the device. You will need to know the PIDs, which you can see with
adb shell b2g-ps
For example if you see that PID 105 is the main process, you could do
adb pull /data/local/tmp/refgraph-105
- In your desktop browser built with refgraph, go to about:refgraph, enter the snapshot filename under "Load snapshot from file:", hit Load, and start playing (e.g. click Cycles Summary).
Detailed usage instructions