UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36

Example URL:
any page

Steps to reproduce the problem:
1. Observe any page

What is the expected behavior?

What went wrong?
Ok, in short:

I see page render split-second freezing with (almost exactly) 10 second repeat regardless of page content.
Any page, even in incognito mode, and even without extensions.
I was able to track it and fix it by turning off auto tab discard in chrome://flags.

Details:
I keep large browser sessions - hundreds of tabs across a dozen windows. I learned to use tab discarding and keep an extension for lazy tab loading.
Some time ago I noticed video stuttering that wasn't affected by connection speed, buffering, or available RAM. CPU didn't seem to be overloaded too.
Sound (from videos or otherwise) is unaffected during a freeze.
Studying it closely I found that every page is affected (it's easy to miss - other reports might not mention it), and CPU spikes happen in main chrome process.

Again, this happens for me even at 5% CPU load, 9 GB available RAM, even if there are only 14 active tabs with simple content (no videos, no games, no ads, etc.) regardless of which site or page it is showing.

I tried:
- running same session with no extensions (issue persists)
- canary with new session (no issues)
- new profile (no issues)

I found that chrome://tracing/ for JS and rendering showed repeating (~600ms every 10 secs) call to Start() at tab_manager.cc.

Disabling "Automatic tab discarding" in chrome://flags fixes it.
(Tab discards via extensions cause no issues)

If it helps, studying Chrome processes shows a small CPU spike (no overloads) in main process and a dip in I/O in some other processes at the time when stutter occurs.

Does it occur on multiple sites: Yes

Is it a problem with a plugin? No 

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 68.0.3440.106  Channel: stable
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: