Safari 9 on OS X 10.10.5 spikes CPU, floods console with logs

Originator:michele.titolo
Number:rdar://23037471 Date Originated:10/8/2015
Status:Open Resolved:
Product:Safari Product Version:9.0 (10601.1.56.2)
Classification:Power Reproducible:Always
 
Summary:
After the last OS X update, Safari has started eating up CPU, about 100% of it, and excessively logging this one particular message. Opening Console to view the logs makes it worse since then Console starts taking up 100+% of CPU. This does not show up as "using significant energy" though it definitely has caused my battery life to diminish.

I've attached screenshots from Activity Monitor and Console.


*Note: I cannot update to 10.11 to fix this because the iOS 7 Simulator, which I need for my job, does not run on 10.11*

Steps to Reproduce:
1. Open Safari
2. Click in the launch bar
3. Search, type in a URL, or load a bookmark (basically do anything to get the suggestions dropdown).
4. Go to site
5. :-O

Expected Results:
I expect Safari to not take up 100% of cpu unless some heavy, intense calculation is going on (which should be rare).

Actual Results:
Safari eats up a bunch of CPU for seemingly no reason

Version:
OS X 10.10.5 (14F27)
Safari 9.0 (10601.1.56.2)

Comments

I remember having an issue on 10.10 where having Top Sites enabled made my computer spike lots of CPU usage. Maybe it's related.

By zorgiepoo at Oct. 10, 2015, 3:52 a.m. (reply...)

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