This is awesome. We've talked about how much we've wanted this since the early days of MemShrink back in 2011. Thanks to everyone who was involved.
- Kyle On Thu, Jan 14, 2016 at 1:50 PM, Nick Fitzgerald <nfitzger...@mozilla.com> wrote: > Hi folks! > > Dominator trees give you fine-grained insight into memory retention. > > In a graph rooted by some node R, a node A is said to dominate B iff every > path to B starting from R passes through A. In the context of a heap graph, > another way to say this would be that A is retaining B: if the garbage > collector found A to be unreachable and eligible for reclaiming, than B > would also be unreachable and eligible for reclaiming. > > We also use this to calculate the "true" memory cost of a node in the heap > graph. This is the "retained size" and contrasts with the naive "shallow > size". For example, imagine a large binary tree where there are no outside > references into subtrees, only to the root. The root node itself has a > small shallow size: a left branch pointer, a value, and a right branch > pointer. However, it is retaining the whole rest of this large tree's > structure, and so its retained size is significant. > > Here is a screenshot of the dominator tree (combined with allocation stack > tracking) in action to debug the memory overhead of loading large source > files in a CodeMirror editor: http://i.imgur.com/sGsVJb9.png > > And here is a reminder of how to enable to memory tool within the > devtools: http://i.imgur.com/hEPTqrT.png > > 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: > https://developer.mozilla.org/en-US/docs/Tools/Browser_Toolbox > > Please try it out, give me your feedback, and file bugs in the "Firefox" > product and "Developer Tools: Memory" component! > > My thanks to the folks who reviewed patches for this feature: Jordan > Santell, Steve Fink, Boris Zbarsky, and Jim Blandy. > > Cheers, > > Nick > > _______________________________________________ > firefox-dev mailing list > firefox-...@mozilla.org > https://mail.mozilla.org/listinfo/firefox-dev > > _______________________________________________ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
