1082849 - [e10s] [meta] Performance improvements for add-on shims

Status: RESOLVED FIXED

(Firefox :: Extension Compatibility, defect)

Description

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

This bug will cover any performance improvements we may want to do for add-on shims. The initial idea is to cache frequently accessed properties of DOM nodes. This will help a lot with bug 1073664, which I think is causing a lot of add-on jank.

We decided in the meeting today to mark this m4 since it causes people with certain common add-ons to have a terrible experience with e10s.

Comment 1

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

See bug 1084091.

Comment 2

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

I filed some bugs to improve the performance of Adblock. Using my testcase (https://www.youtube.com/watch?v=QvqiiUmb9rk), here are the improvements:

baseline:      49492 CPOW messages
+ bug 1091959: 30626
+ unfiled bug: 19105  <--- it turns out I had missed a return statement somewhere and it
                           caused us to send lots of extra messages.
                           the fix is folded into bug 1091970.
+ bug 1091964: 16837
+ bug 1091970: 8100

Unfortunately, I didn't really observe any noticeable effect from all these improvements. However, I then starting testing with http://www.huffingtonpost.com/2014/10/29/matt-taibbi-first-look_n_6066690.html. These are the rough pageload times I get for that page:

No e10s, no adblock: ~1.8 sec
No e10s, with adblock: ~1.8 sec
E10s, no adblock: ~2.5 sec
E10s, with adblock, with my fixes: ~3.0 sec
E10s, with adblock, without my fixes: ~5.0 sec

I also noticed that the page is somewhat unresponsive immediately after being loaded with adblock and e10s. My patches help with that somewhat, but they don't get us to the point we are without adblock (or without e10s). I haven't figured out how to measure that though.

There's a lot more work to be done, but this is a start. I want to look at LastPass tomorrow.

Comment 5

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Going to close this. We're not focusing on it anymore.