hmm is this a regression? my M63 device seems to have memory info on android processes

This bug is specifically about Memory Footprint, not the old Memory column.

+ lalitm, hjd, primiano.

Theoretically we're just grabbing data from memory_instrumentation service. This suggests that the service isn't working correctly.

Let me see if I understand correctly, is this about Android processes running in the Arc++ containers not showing now in task manager?

I had no idea that we ever supported that, that might have worked by accident, if it ever worked.

Nobody here in LON has any ideas on ARC++ architecture, nor any devices to test. 
We need somebody familiar with ARC++ architecture and debugging to look into this. 

+hirono, who works on ARC++ and might be able to direct us appropriately. 

lhchavez@ - Could you reassign the issue to someone who is familiar with ARC processes management?

So on M64 I see two memory columns and one (new one) is not populated for ARC++ processes.

where is this getting populated?

so this is a regression

cylee, can you take a look?

This column was newly added to the task manager, so I'm not sure if this is a regression, but we should get it fixed. 

The service logic is here: https://cs.chromium.org/chromium/src/services/resource_coordinator/memory_instrumentation/coordinator_impl.cc

And the client logic is here: https://cs.chromium.org/chromium/src/services/resource_coordinator/public/cpp/memory_instrumentation/client_process_impl.cc

Relevant function call:
https://cs.chromium.org/chromium/src/services/resource_coordinator/public/cpp/memory_instrumentation/client_process_impl.cc?l=137

I think the problem is that the memory instrumentation service does not know about the existence of ARC++ processes because there is no ClientProcessImpl instance created for them which registers with the existence of a process with the service. 

Examples of creation:
browser: https://cs.chromium.org/chromium/src/content/browser/browser_main_loop.cc?l=1787
child: https://cs.chromium.org/chromium/src/content/child/child_thread_impl.cc?l=517

+cmtm@, who will be owning ARC's memory management.

Thanks to erikchen@ and lalitm@. I checked the code and it looks like we should register ARC processes to the coordinator somewhere, maybe somewhere like 
UpdateProcessList() https://cs.chromium.org/chromium/src/chrome/browser/task_manager/providers/arc/arc_process_task_provider.cc?rcl=4c52579f63f63577695cd447296ceb9de57773a1&l=46

I can do it but I won't have bandwidth very soon, does anybody want to take it over?

I can take it over. Feel free to assign the bug to me.

This bug has an owner, thus, it's been triaged. Changing status to "assigned".

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960

commit 1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960
Author: Willie Koomson <wvk@google.com>
Date: Tue Oct 30 19:33:32 2018

Add memory footprint for Arc processes in task manager

This change adds memory footprint information for Arc processes into the
chrome task manager. ArcProcessService requests a global dump from
Android, and upon receipt provides it to the task manager (through
ArcProcessTaskProvider)

BUG= 799538 
TEST=Manual, compared memory footprint in task manager to top

Change-Id: I5e10ba05e28185de750b6deb2f46d9227d4cc751
Reviewed-on: https://chromium-review.googlesource.com/c/1263335
Commit-Queue: Willie Koomson <wvk@google.com>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Erik Chen <erikchen@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603983}
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/BUILD.gn
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/chromeos/arc/process/arc_process_service.cc
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/chromeos/arc/process/arc_process_service.h
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/metrics/process_memory_metrics_emitter.cc
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/metrics/process_memory_metrics_emitter_unittest.cc
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/profiling_host/background_profiling_triggers.cc
[add] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/arc_shared_sampler.cc
[add] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/arc_shared_sampler.h
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/task_group.cc
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/task_group.h
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/task_manager_impl.cc
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/chrome/browser/task_manager/sampling/task_manager_impl.h
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/components/arc/common/BUILD.gn
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/components/arc/common/process.mojom
[modify] https://crrev.com/1b9a3a4b9fb5e717cf8b210ff9cfd17867bb9960/services/resource_coordinator/public/mojom/memory_instrumentation/memory_instrumentation.mojom