Maby I'm going senile -but really cool min-effect now

[effenberg0x0]

1) I have tested 10's of supposedly "heavy" websites now. I couldn't find other websites that cause the CPU usage to increase as much as it does on OMGUbuntu. But there's nothing unique about the website: Look at the sources, the scripts, use chrome developers tools, profile it, it's pretty much standard;

2) I believe only Chrome/Chromium Browser is affected. FF is OK for me, so is Opera;

3) It looks like the the website does not cause any effect on Windows (IE/Chrome/Firefox tested) and Android (Chrome/Firefox tested). I don't have other Linux to test. It *seems* to be either Linux specific or Ubuntu specific;

4) It *seems* to not affect (or not affect so strongly) PP with Intel VGA;

5) And, the most absurd of all, it seems to be more severe on machines with NVidia VGA.

It doesn't make sense. I have to be wrong in at least one of these, preferably all.

[VinDSL]

Upgraded Chromium from ver 20.x -> 23.x

Troublesome web sites are now rendering nicely, DISQUS is working fine, but CPU usage is still max'ed out.

I guess this is as good as it gets...

[VinDSL]

5) And, the most absurd of all, it seems to be more severe on machines with NVidia VGA.[...]

Maybe not so absurd, after all...

Try this:

• Open 2 tabs (only) in Chromium.
• In the first tab, navigate to http://www.omgubuntu.co.uk/tag/quantal
• In the second tab, open "About Chromium".

Sitting idle in the first tab (OMGUbuntu), this machine uses 90-100% CPU.

Sitting idle in the second tab ("About Chromium"), CPU drops to 20-30%.

Switching tabs back n' forth makes the CPU useage motorboat up n' down.

I *think* this has something to do with the way Chromium/Chrome handles tabs (e.g. if one tab crashes, the other doesn't) but also the way nVidia handles these mutually exclusive processes.

Heh! You're right! Sounds crazy, doesn't it?

[stoneguy]

I'm using Chrome-22 with NotScript add-on in Precise on a quad-CPU box. When OMGUbuntu scripts are allowed, ps shows nearly 60% CPU in use when that tab is open. If I block OMGUbuntu, it's down to under 5%. My money is on a Chrome problem.

Anyone else try NotScript?

[effenberg0x0]

Maybe if we could find other websites that cause a similar effect (I tried a lot and couldn't). I tried embedded videos in many format, audio, flash, HTML5, heavy Javascript, etc...

How would we report a potential problem in Chrome/Chromium, which might or not be more severe in Nvidia, but that affects only a single site? I'm still puzzled

Regards,
Effenberg

[effenberg0x0]

I'm using Chrome-22 with NotScript add-on in Precise on a quad-CPU box. When OMGUbuntu scripts are allowed, ps shows nearly 60% CPU in use when that tab is open. If I block OMGUbuntu, it's down to under 5%. My money is on a Chrome problem.

Anyone else try NotScript?

I'm gonna try it. I disabled Javascript in chromium developer tools and noticed a decrease in CPU usage, but OMGUbuntu still takes the CPU much above normal usage in comparison to all websites I tested. It's really weird. Are you using a Nvidia VGA or Intel/ATI?

Regards,
Effenberg

[stoneguy]

This system has AMD A8-3820 APU with Radeon HD Graphics. And I'm using the No Effects desktop. On Precise.

Right-click on the top-of-screen slide show to bring up the DOM inspector, and you'll see the CPU drop when it opens, and shoot back up when it's closed. I'm suspecting it's connected to the class=menu-banner-menu-container block. Beyond that my understanding runs out

[ventrical]

On firefox I have 20 tabs open. Everything is normal until omgubuntu tab is open, Then it pulls on both cores.

GEForce218/210.

[stoneguy]

Well, I think there are enough observations to stick my neck out and contact OMGUbuntu. I submitted the following on their contact form.

Excessive CPU utilization when viewing your site
-------------------------------------------------------------
Some members of an Ubuntu testing team have noticed some strange behaviour, particularly when viewing your site in Chrome.

Please see the launchpad thread http://ubuntuforums.org/showthread.p...6#post12269566
for details.

Maybe they'll wrestle with it for awhile and contact the Chrome developers themselves.

[joey-elijah]

Well, I think there are enough observations to stick my neck out and contact OMGUbuntu. I submitted the following on their contact form.

Maybe they'll wrestle with it for awhile and contact the Chrome developers themselves.

Which I just read, thanks

I'll try to explain it from my understanding (bear in mind that I'm not the web dev)

Originally we assumed that because the slider-banner can accelerate using OpenGL (which I believe is what's needed to make it scale properly when you resize the width of the window) that the CPU load was a hardware-related issue for a small % of people.

Then we did some digging, testing and found that it was more likely to be the result of this bug in Chromium Webkit that causes excessive CPU spikes when a CSS transition happens:

• http://code.google.com/p/chromium/is...tail?id=128321

Because the OMG! slider is on a 5-second loop the result is that we're perpetually creating CPU spikes (CPU spikes for 2 seconds, starts to fall for 1, then spikes again for 2, repeat)

We turned the transitions off and CPU usage fell to round-about-normal %'s.

Edit:

It'd be helpful if you folks could see if the slider/main page load on your CPU is better, worse, or the same @ http://d0od.staging.wpengine.com/ (Do stay on the main page as posts are linked to their production server equivalents).

Then look again on omgchrome.com.

OMG! Chrome! & OMG! Ubuntu! use the same themes/configs but the Chrome site gets updates/changes first. (chrome staging -> chrome production -> omgubuntu production)

I'll pass this thread on to the web-dev anyway. We want this fixed ASAP.

(Disqus on the other hand is a law unto itself, so I can't comment. I swear the weather affects it some times... )