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 --- - [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 <!-- Reviewable:start --> --- This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/17192) <!-- Reviewable:end -->		2017-06-07 19:57:57 -07:00
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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