UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36

Example URL:

Steps to reproduce the problem:
We have a specific page on an internal web application that is very DOM-heavy (~2k DOM elements) and uses a lot of CSS shadows and opacity.

When I open the page, CPU usage immediately climbs to ~60%, and stays there. When I switch to a different tab in Chrome, usage drops. When I open the tab again, usage immediately climbs back to 60%.

I have no Chrome extensions, no other tabs open, and no other programs running.

Some data points:

- According to Timeline and CPU profilers in devtools, the page is neither using the CPU or allocation objects when it is left open.
- According to Process Explorer and Performance Monitor, CPU usage is around 60% (around 1/3 of that is kernel mode, 2/3 is user mode)
- According to Chrome Task Manager, the Browser is consistently using 59% CPU, and the guilty tab is consistently using 0-5%

Chrome is running inside of a Xen instance. This issue does not happen on OSX.

Machine params:

- Windows 7 Enterprise x64
- Intel Xeon dual core @2.60GHz
- 8GM RAM

Possibly related:

- https://bugs.chromium.org/p/chromium/issues/detail?id=23523
- https://bugs.chromium.org/p/chromium/issues/detail?id=447583

Attempted fixes:

- Tried toggling all Chrome flags mentioned here: http://superuser.com/a/697573/47999

What is the expected behavior?

What went wrong?
See Devtools timeline (CPU usage spikes when page is loaded, which is expected, but then goes down to zero, while external tools still report it as pegged around 60%).

Also see Process Explorer and Chrome Task Manager screenshots attached.

Does it occur on multiple sites: N/A

Is it a problem with a plugin? No 

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 54.0.2840.71 m (64-bit)  Channel: stable
OS Version: 7 Enterprise
Flash Version:
 

Deleted: Screen Shot 2016-10-24 at 2.30.03 PM.png 58.4 KB

	Screen Shot 2016-10-24 at 2.30.03 PM.png 58.4 KB View Download

Deleted: Screen Shot 2016-10-24 at 2.36.22 PM.png 110 KB

	Screen Shot 2016-10-24 at 2.36.22 PM.png 110 KB View Download

Deleted: Screen Shot 2016-10-24 at 1.42.57 PM.png 43.3 KB

	Screen Shot 2016-10-24 at 1.42.57 PM.png 43.3 KB View Download