This project's goal is to create a BrowserPlus[1] plugin to profile Javascript.

Service Description:

A service that analyzes the memory and cpu usage of a web browser. The service can take 1 sample or multiple samples at a specified
interval. When sampling at intervals, at most 1,000 samples are taken. If you provide a callback function, your javascript will be called
after every sample is taken. If no callback is provided, all samples are stored in an array and returned after start() completes or stop()
is called.

The sample object is a map with the following keys (most values are floats):

* [sample] - the sample number (1-1,000)
* [time]   - the string representation of the time the sample was taken
* [sys]    - the percentage CPU "sys" processes are using
* [user]   - the percentage CPU "user" processes are using
* [ffxcpu] - the percentage CPU Firefox is using, or -1.0 if it is not running
* [ffxmem] - the amout of memory Firefox is using, or -1.0 if it is not running
* [safcpu] - the percentage CPU Safari is using, or -1.0 if it is not running
* [safmem] - the amout of memory Safari is using, or -1.0 if it is not running


Sample of data:
------------------------------------------------------------
Sample #      : 70
Time          : Sat Dec 13 00:36:45 -0800 2008
System CPU    : 4
User CPU      : 7
Firefox CPU   : 0
Firefox Memory: 78413800
Safari CPU    : 2.8
Safari Memory : 32768000
------------------------------------------------------------

Right now it's a hack, no, a kludge that's brittle, ugly and smells bad.
It's osx/ffx only.

How to get the service installed see the README.txt in:
src/service/README.txt


[1] http://developer.yahoo.com/browserplus