1628033 - About:Memory does not list a PID for Main Process and Socket Process

Status: RESOLVED FIXED

(Toolkit :: about:memory, defect, P3)

Description

[Leman Bennett [Omega]]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0

Steps to reproduce:

Main Process has not had a PID listed for a while but Socket Process is fairly new. Its much easier to track down the processes when there's a PID attached.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:njn, could you have a look please?

For more information, please visit auto_nag documentation.

Comment 2

[Nicholas Nethercote [inactive]]

Attachment: Bug 1628033 - Add pid to the socket process in about:memory. r=valentin

This is modelled on the corresponding code in
RDDParent::RecvRequestMemoryReport().

Comment 3

[Nicholas Nethercote [inactive]]

Adding the PID to the socket process is easy and I have uploaded a patch for it.

The main process is harder, because it gets special treatment -- normal memory reporters use an empty string for the process name and then about:memory turns that into "Main Process". Is it possible to get the main process pid from JS chrome code?

Comment 4

[Nicholas Nethercote [inactive]]

Is it possible to get the main process pid from JS chrome code?

Services.appinfo.processID does the trick!

Comment 5

[Nicholas Nethercote [inactive]]

Services.appinfo.processID does the trick!

Hmm, no, that won't work. E.g. if we load memory reports from file, we need the PID from when they were saved, not the current PID, because they may have been saved in a different invocation of Firefox (possibly even on a different machine).

Comment 6

[Nicholas Nethercote [inactive]]

Oh, interesting: if you get live measurements by pressing the "Measure..." button, you just get "Main Process" for the main process. But if you do "Measure and save..." and then subsequently load, you get "Main Process (pid XYZ)", due to this code.

Comment 7

[Nicholas Nethercote [inactive]]

Attachment: Bug 1628033 - Add pid to the main process in about:memory. r=erahm

In the tests we now explicitly use "Main Process" (or similar) for the process
name in various places to avoid having to filter out a PID.

Also in test_aboutmemory[34].xhtml, the main process entries now appear
first, as they should, because the sorting code now looks for a "Main Process"
prefix, rather than an exact match.

Depends on D72995

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/5112f6a72171
Add pid to the socket process in about:memory. r=valentin,necko-reviewers
https://hg.mozilla.org/integration/autoland/rev/693d927ca216
Add pid to the main process in about:memory. r=erahm

Comment 9

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/5112f6a72171
https://hg.mozilla.org/mozilla-central/rev/693d927ca216