1337080 - Switch GMP initialization to be asynchronous

Status: RESOLVED WONTFIX

(Core :: Audio/Video: GMP, defect, P4)

Description

[(no longer active)]

PGMPService::Msg_LaunchGMP can take a long time:

<https://telemetry.mozilla.org/new-pipeline/dist.html#!cumulative=0&end_date=2017-02-05&keys=PGMPService%253A%253AMsg_LaunchGMP!PContent%253A%253AMsg_RpcMessage!PContent%253A%253AMsg_GetGfxVars!PAPZCTreeManager%253A%253AMsg_ReceiveMouseInputEvent&max_channel_version=nightly%252F54&measure=IPC_SYNC_LATENCY_MS&min_channel_version=null&product=Firefox&sanitize=1&sort_keys=submissions&start_date=2017-02-02&table=0&trim=1&use_submission_date=0>

Start	End	IPC_SYNC_LATENCY_MS Count
0	1	0 (0%)
1	3	2.13k (27.11%)
3	8	270 (3.44%)
8	20	130 (1.66%)
20	50	1.16k (14.72%)
50	126	2.39k (30.44%)
126	317	891 (11.35%)
317	796	529 (6.74%)
796	2k	263 (3.35%)
2k	Infinity	94 (1.2%)

Comment 1

[Chris Pearce [:cpearce (Not reading bugmail)]]

Note: we make the sync call to LaunchGMP on the GMP thread, not on the main message loop thread. Does that mean that the other threads involved in IPC and the main thread, aren't affected by this sync IPC message?

Comment 2

[(no longer active)]

(In reply to Chris Pearce (:cpearce) from comment #1)
> Note: we make the sync call to LaunchGMP on the GMP thread, not on the main
> message loop thread. Does that mean that the other threads involved in IPC
> and the main thread, aren't affected by this sync IPC message?

I think so.  It's a bit annoying that these messages are all lumped into the same telemetry probe (for main thread vs non-main thread case.)

Comment 3

[Anthony Jones (:ajones, :kentuckyfriedtakahe, :k17e)]

This doesn't block any main threads so it isn't urgent but it is possible for one GMP to block another.

Comment 4

[Chris Pearce [:cpearce (Not reading bugmail)]]

Since this is off-main-thread, I'm de-prioritizing this to P3.

Comment 5

[Bulk Bug Changes for mreavy's org]

Mass change P3->P4 to align with new Mozilla triage process.

Comment 6

[Chris Pearce [:cpearce (Not reading bugmail)]]

I'm going to WONTFIX this. Doing a sync launch on the GMP thread won't block other threads, so this should be benign.