tree 30399c92573562854e0bdeef4638f813a9f6cbdc
parent f2ddfefdb51d1c933b6f8e2e1a88f603d0bfdc12
author David 'Digit' Turner <digit@google.com> 1602798055 +0200
committer Commit Bot <commit-bot@chromium.org> 1606517657 +0000

gn recipe: Link GN with rpmalloc to speed it up.

NOTE: This is a reland of [1] with an updated rpmalloc
revision that includes fixes for the -Wconversion errors
that required reverting the original CL.

This CL changes the GN recipe to link the executable with the
rpmalloc allocator from https://github.com/mjansson/rpmalloc

This speeds up the 'gn gen' operation of both Chromium and Fuchsia
operations by 28% and 12% respectively [1], and has slightly better
performance than using tcmalloc from gperftools in the Fuchsia case.

Note that:

- The sources are grabbed directly from github.com, but it might be
  desirable to use a Chromium or Fuchsia supported mirror instead.

- Only Linux has been tested so far, so only this platform enables
  this build mode.

[1] Median measurements from 10 runs of 'gn gen' using the default
    Linux allocator (glibc), gperftools' tcmalloc, and rpmalloc:

  Fuchsia:
      glibc (default):  9917 ms
      gperftools:       7858 ms  (26% faster)
      rpmalloc:         7752 ms  (28% faster)

  Chromium:
      glibc (default):  4742 ms
      gperftools:       4186 ms  (13% faster)
      rpmalloc:         4235 ms  (12% faster)

[1] https://gn-review.googlesource.com/c/gn/+/9920

Change-Id: I0860c34437faee7c1f97e01f831cbf25f49c819e
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/10420
Commit-Queue: David Turner <digit@google.com>
Reviewed-by: Petr Hosek <phosek@google.com>