servo/components/layout_thread
bors-servo c0f3ec8780 Auto merge of #17192 - mbrubeck:layout, r=pcwalton
Parallel layout optimizations

This takes some of the optimizations made to parallel styling in #16971 and applies them to parallel layout.  Specifically:

* Reduce the chunk size, to increase chances for parallelism on trees with small fan-out.
* Reduce allocations by using SmallVec.
* Reduce task switching by processing up to one chunk of children within the same rayon task as the parent.

This cuts the "Primary Layout Pass" time in **half** on the MySpace page from [tp5n], and on my other real-world test pages it is a small improvement or close to no change.

[tp5n]: https://wiki.mozilla.org/Buildbot/Talos/Tests#tp5n_pages_set

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they affect performance only

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2017-06-07 19:57:57 -07:00
..
Cargo.toml Bump euclid to 0.13 and heapsize to 0.4 2017-06-05 19:28:39 +02:00
lib.rs Auto merge of #17192 - mbrubeck:layout, r=pcwalton 2017-06-07 19:57:57 -07:00