Traces are visible on crash, which ease a lot investigating outliers.
I suspect traces are not symbolized, which mean the developer need to manually download them and symbolize them to be human-readable.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c2a5f13c857cb5e7118b362bd76b1e3e7be6068d

commit c2a5f13c857cb5e7118b362bd76b1e3e7be6068d
Author: erikchen <erikchen@chromium.org>
Date: Wed Aug 16 20:30:13 2017

Emit a compressed dump from the profiling process.

The browser process passes an open file handle to the profiling process, which
then uses zlib to populate the contents of the file.

Bug:  753519 
Change-Id: I73e8090c073302ca2549efe6c54eac8cb43ea214
Reviewed-on: https://chromium-review.googlesource.com/616175
Commit-Queue: Erik Chen <erikchen@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
Cr-Commit-Position: refs/heads/master@{#494925}
[modify] https://crrev.com/c2a5f13c857cb5e7118b362bd76b1e3e7be6068d/chrome/browser/profiling_host/profiling_process_host.cc
[modify] https://crrev.com/c2a5f13c857cb5e7118b362bd76b1e3e7be6068d/chrome/profiling/BUILD.gn
[modify] https://crrev.com/c2a5f13c857cb5e7118b362bd76b1e3e7be6068d/chrome/profiling/DEPS
[modify] https://crrev.com/c2a5f13c857cb5e7118b362bd76b1e3e7be6068d/chrome/profiling/memlog_connection_manager.cc

> The heap dumps should at least be symbolizable and serve as functional input to diff_heap_profiler.py.

This works on macOS, and I believe ajwong confirmed that it works on Linux.

yup. closing for now.