tree bc4d3312ff5a13349921ef12bcf02dff47f604aa
parent 915a7d565161cc1ef14a37100e175862efd5cd0d
author Darshan Sen <raisinten@gmail.com> 1656078654 +0530
committer Copybara-Service <copybara-worker@google.com> 1656085591 -0700

Reland "posix: Replace DoubleForkAndExec() with ForkAndSpawn()"

This is a reland of 460943dd9a71dc76f68182a8ede766d5543e5341

Original change's description:
> The DoubleForkAndExec() function was taking over 622 milliseconds to run
> on macOS 11 (BigSur) on Intel i5-1038NG7. I did some debugging by adding
> some custom traces and found that the fork() syscall is the bottleneck
> here, i.e., the first fork() takes around 359 milliseconds and the
> nested fork() takes around 263 milliseconds. Replacing the nested fork()
> and exec() with posix_spawn() reduces the time consumption to 257
> milliseconds!
>
> See https://github.com/libuv/libuv/pull/3064 to know why fork() is so
> slow on macOS and why posix_spawn() is a better replacement.
>
> Another point to note is that even base::LaunchProcess() from Chromium
> calls posix_spawnp() on macOS -
> https://source.chromium.org/chromium/chromium/src/+/8f8d82dea0fa8f11f57c74dbb65126f8daba58f7:base/process/launch_mac.cc;l=295-296

The reland isolates the change to non-Android POSIX systems because
posix_spawn and posix_spawnp are available in Android NDK 28, but
Chromium is building with version 23.

Change-Id: I5a9253ad7d21a18dc74158d74bdec96beef78c20
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/3721655
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Mark Mentovai <mark@chromium.org>
GitOrigin-RevId: 1c37daa5acd500633cdffc7f6db61d8c6b32b771