tree e60c500b38f24081080ae6c761ac333746e114c6
parent b25b458504c238958931d2f2aae891aaa40f9bf8
author Ryan Macnak <rmacnak@google.com> 1623357573 +0000
committer commit-bot@chromium.org <commit-bot@chromium.org> 1623357573 +0000

[vm, profiler] Increase the number of frames per Sample.

In practice, the Dart stack is usually much deeper than 8 frames, causing a typical tick to chain multiple Samples together. Increasing the number of frames covered by a Sample causes the typical tick to waste less memory on the non-frame portions of linked Samples.

For a run of dart2js compiling hello_world, increasing the frames-per-Sample from 8 to 32 decreases the memory required to represent all the ticks from 11930560 to 6907120 (-42%), with diminishing returns thereafter.

This CL does not make a compensating decrease the default number of Samples in the buffer, so it has the effect of increasing the time range covered by the buffer for deep stacks by ~4x while only increasing memory usage a bit less than 2x.

TEST=ci
Change-Id: I60b17263dcb900fff4198ca6039753828295bf38
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/202308
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>