That sounds very useful.
Any chance we can get the same kind of output on the console in case of
mochitest memory leak?
On 03/11/15 23:32, Nick Fitzgerald wrote:
> Hi folks!
> (Jordan Santell made an announcement on the devtools mailing list,
> but I thought I'd spread the word around.)
> The first iteration of the new heap snapshots memory tools landed on m-c
> in the middle of the last cycle and rode the train to Developer Edition
> with the merge.
> This tool is built on top of JS::ubi::Node which is an API to do
> analyses on the heap graph as the GC sees it, and the SavedFrame JS
> stack recording.
> In this first release, the most notable feature is capturing the JS
> stack when objects are allocated so that you can see exactly where your
> retained objects are coming from. The downside is that this incurs
> overhead and you have to start recording allocation stacks *before* you
> start saving heap snapshot. You can also disect the heap into various
> other buckets.
> This initial version is very much just getting something out the door
> and there is a ton more coming down the pipe. Filtering/searching and
> diffing snapshots are in the works at the moment. Currently, we don't
> take advantage of our full access to every node and edge in the heap
> graph. Soon, we will compute dominator trees to find "deep" size /
> retention as well as find the first N shortest paths from GC roots to
> objects of interest. We are also planning on adding support for cycle
> collected nodes and edges to the JS::ubi::Node graph.
> You can enable the new tool by going to the settings panel of the
> devtools and checking the "Memory" checkbox on the left underneath
> "Default Firefox Developer Tools".
> If you would like to use this tool for the whole runtime rather than
> scoped to a single tab, use the browser toolbox. Here are instructions
> for enabling and using the browser toolbox:
> Please try it out and file bugs in the "Firefox" product and "Developer
> Tools: Memory" component! We want this to be a useful tool for _you_!
> firefox-dev mailing list
David Rajchenbach-Teller, PhD
Performance Team, Mozilla