479930 - hulu.com video choppy when zoomed, CPU usage significantly higher

Status: RESOLVED WONTFIX

(Core Graveyard :: Plug-ins, defect, P5)

Description

[Myk Melez [:myk] [@mykmelez]]

In Firefox 3.0.6, a video on hulu.com plays smoothly, and the CPU usage of Firefox during playback, as reported by Activity Monitor, is in the 50s-80s. But in the latest Shiretoko nightly, the video plays choppily, and the CPU usage of Shiretoko during playback is in the 90s-120s.

Steps to Reproduce:

1. go to a video on hulu.com (f.e. <http://www.hulu.com/watch/45/buffy-the-vampire-slayer-i-robot-you-jane#x-0,vepisode,1>);
2. after the initial commercial, once the video starts playing, pause the video and wait for it to become adequately buffered (to remove bandwidth as a factor when diagnosing the problem);
3. unpause the video and start watching it.

Expected results: the video plays back smoothly, and CPU usage stays within the 50s-80s.

Actual results: the video plays back choppily, and CPU usage is in the 90s-120s.

Note: I don't always see the choppiness; it seems to come and go.  Also, I mostly tested with the hi-res (480p) option (for that, press the Watch in Hi-Res button before pausing the video for buffering).  Nevertheless, I do see the higher CPU usage with both the std-res and the hi-res options.

Nominating for blocking, as this is a noticeable regression to a popular website.

Comment 1

[Damon Sicore (:damons)]

Can we get a regression range?

Comment 2

[Myk Melez [:myk] [@mykmelez]]

I haven't narrowed it down more yet, but I just tested 3.1b1 and 3.1b2, and 3.1b1's CPU usage was the same as 3.0's (i.e. in the 50s-80s range) while 3.1b2's was the same as the latest nightly's (i.e. in the elevated 90s-120s range), so it looks like this is a regression between b1 and b2.

Comment 3

[Mike Beltzner [:beltzner, not reading bugmail]]

FWIW, I don't get to use Hulu much, and had previously assumed that this just fell into the general "sometimes Places caches out and that results in the chunkiness on video playback on sites like YouTube" category.

Last night, however, I witnessed the evil alien plot that is Hulu, and noticed that this bug is very pronounced, and different than general video choppiness. As Myk says, right after coming back from commercial, the video gets choppy for a few seconds, then gets OK again. My alien plot is disturbed!

Comment 4

[Myk Melez [:myk] [@mykmelez]]

I did some more investigation, and the CPU usage is a regression between 11/04 and 11/05, specifically Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b2pre) Gecko/20081104 Minefield/3.1b2pre and Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.1b2pre) Gecko/20081105 Minefield/3.1b2pre.

Comment 5

[Johnny Stenback (:jst)]

Josh, I'd argue that this is a blocker. Can you have a look into this? The date range in the above comment is probably worth looking into. Let me know if you disagree with this being a blocker.

Comment 6

[Josh Aas]

The biggest things going in during 2008-11-04 and 2008-11-05 were tracemonkey merges, media work by Chris Double, and DNS prefetching work. Nothing particularly suspicious.

Comment 7

[Josh Aas]

Attachment: 11/03/2008-11/05/2008 trunk checkins

Comment 8

[Josh Aas]

I have tried to reproduce this myself a few times and I haven't seen anything that strikes me as particularly abnormal. The video does occasionally stutter after commercials but that has always happened to me in a number of different situations. Especially with HD content. I'm not saying this particular bug doesn't exist as a distinct case, just that I don't see it myself as a distinct case.

Comment 9

[Myk Melez [:myk] [@mykmelez]]

After some further testing I realized that this is page zoom-dependent, as it doesn't occur when page zoom is set at 100%.  When I zoom in or out one tick, however, I do see the increased CPU usage.  However, I still don't see it on the 11/04 build, so this seems to be a page zoom-related regression between the 11/04 build and the 11/05 build.

I've created a Shark profile of the latest trunk nightly with a hulu.com video page zoomed out one tick.  The profile samples the firefox-bin process for a couple dozen seconds while the video plays in a single tab in a fresh profile.

http://people.mozilla.com/~myk/bug479930-profile.mshark

Comment 10

[Josh Aas]

I had myk test using the latest 1.9.1 and 1.9.2 nightly builds and Flash 10.0 r22 on a Core 2 Duo MacBook Pro and he said he could reproduce in both cases.

Comment 11

[Johnny Stenback (:jst)]

Ok, given that this is a regression in performance only when zooming the page I don't think this is a blocker for shipping.

Beyond that, I think the best way to track this down is for someone to find the exact commit that caused this regression and go from there. Vlad and I looked at the list of commits, and nothing really stands out. Private browsing UI stuff seems to have landed in the regression range, not sure if that's in any way related though.

Comment 12

[Charles]

This doesn't sound like a Flash Player specific issue if it was introduced in a nightly build.

Comment 13

[Paul Silaghi, QA [:pauly]]

I confirm the hulu videos play choppy when zooming the page (command button + mouse scroll) on Mac OS X 10.8.2 Nightly 21.0a1 (2013-01-27). They seem to work better on Win.

Comment 14

[Mihai Morar, (:MihaiMorar)]

(In reply to Paul Silaghi [QA] from comment #13)
> I confirm the hulu videos play choppy when zooming the page (command button
> + mouse scroll) on Mac OS X 10.8.2 Nightly 21.0a1 (2013-01-27). They seem to
> work better on Win.

Same issue here, using Mac OS 10.8.3 on Latest nightly, all videos play choppy when zooming the page. In addition the loadings are slowly and have a couple of seconds while the videos are delaying. 

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:23.0) Gecko/20130429 Firefox/23.0(20130429030926) 

Flash Player: 11.7.700.169

Comment 15

[Georg Fritzsche [:gfritzsche]]

While i can't play the originally linked video ("not available in your country"), i don't see any notable difference in choppiness or cpu usage between normal and zoomed in.
Worth noting that the Flash element always snaps back to the same size on Hulu.

Comment 16

[Mihai Morar, (:MihaiMorar)]

(In reply to Georg Fritzsche [:gfritzsche] from comment #15)
>  ("not available in your country")

Try trailers, they are avaible all, I had tested on them to see how hulu.com is working in Comment 14

Comment 17

[Mihai Morar, (:MihaiMorar)]

(In reply to MarioMi (:MarioMi) from comment #16)

I could have played the originally linked video, by enabling Use Proxy pref in preferences and using an US proxy and Port.

Comment 18

[Georg Fritzsche [:gfritzsche]]

(In reply to MarioMi (:MarioMi) from comment #16)
> Try trailers, they are avaible all, I had tested on them to see how hulu.com
> is working in Comment 14

That's what i used for comment 15 and i didn't note anything being off.

Comment 19

[BMO Automation]

Resolving as wont fix, plugin support deprecated in Firefox 85.