1956979 - 9s jank trying to run PContent::Msg_CreateAudioIPCConnection while a game is paused in the background (win10)

Status: ASSIGNED

(Core :: Audio/Video: Playback, defect, P3)

Description

[Randell Jesup [:jesup] (needinfo me)]

I hit a 9s Jank when opening tabs on Windows 10 when the game Kingdom Come Deliverance 2 was running, paused, in the background.
I hit this every time I clicked on one of the black dots in the scatter graph on https://bringatrailer.com/triumph/wedge/. Note that I don't see any reason for this page to do audio unless I click on a video.

https://share.firefox.dev/3FHLM4s
9s main process MainThread jank loading a page in a new tab (after the page paints - I noticed I couldn't scroll)
audio is headset (wired)

The next day, without restarting the browser, but having exited (and re-entered) the game, I no longer see the pause.

Firefox Nightly.

Comment 1

[Matthew Gregan [:kinetik]]

Thanks for reporting this. There's work underway via bug 1899317 to move the AudioIPC server out of the parent process, which will remove any MainThread interactions and address the jank issue.

Aside from that, these calls should not be taking 9 seconds, so there's something wrong inside the AudioIPC server thread. Unfortunately the media threads are missing from the profile, so it's hard to know what's causing the server thread to take so long to reply. If you happen to hit this again, please record it with the Media preset as that should capture all AudioIPC-related threads.