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[display_list] grow display list backing store by power of two.
Fixes https://github.com/flutter/flutter/issues/157108
Right now the DL is always growing by a minimum 4096 bytes at a time. On applications with large display lists, this can lead to hundreds of reallocations as the display list is build, as long as each draw op is small. For example, the framework benchmark long picture scrolling draws many lines, each of which is a pretty small op.
Update the code so that we grow by doubling, with a minimum increment of ~16K
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I believe you changed drawVertices to not copy into the display list. drawPoints/drawAtlas still embed their data right?
I believe you changed drawVertices to not copy into the display list. drawPoints/drawAtlas still embed their data right?
Anything that uses CopyV in dl_builder.cc could potentially have a very large size. I didn't double check, that list was off the top of my head...
The benchmark to watch is https://flutter-flutter-perf.skia.org/e/?begin=1727976394&end=1729696415&queries=test%3Dvery_long_picture_scrolling_perf_ios__e2e_summary&requestType=0&selected=commit%3D42943%26name%3D%252Carch%253Dintel%252Cbranch%253Dmaster%252Cconfig%253Ddefault%252Cdevice_type%253DiPhone_11%252Cdevice_version%253Dnone%252Chost_type%253Dmac%252Csub_result%253D99th_percentile_frame_rasterizer_time_millis%252Ctest%253Dvery_long_picture_scrolling_perf_ios__e2e_summary%252C
reason for revert: unexpected framework ui thread regression, no performance improvement