Q: Safari Web Content high CPU usage

Have you (or anybody else) reported this bug to Apple ?

In my case the cause of 100% CPU usage of Safari was Trusteer Endpoint Protection plugin. Turning it off in the System Preferences solved the problem. It is worth to mention that CPU usage problem appeared with Maverics upgrade, so I doubt that the culpruit is Trusteer.

In my case was the fastestube extension, when started Facebook, I uninstalled it, and voilá! Everything goes perfect now!!!

I have been having similar prolems and have tried many of the proposed solutions on this post and others with no effect. I have cleaned out all website data, turned off all extensions, etc.. While investigating this problem, I have had only one tab open and still my CPU was running at 100%. I came across an old post http://forums.macresource.com/read.php?1,1120323,1124043 and out of desparation decided to try it. This involves deleting the folder HD > Library > Google. It Worked!! My Safari Web Content usage dropped from 100% to 2.1%. I did not zip the folder before putting it in the Trash. I still have a couple of QTKitServer Safari Web Contents (Not Responding), but everything appears to be running as expected with 87% idle CPU.

After reading this discussion thread and trying numerous tips, I didn't resolve my issue. However, the ideas presented got me looking around in areas I hadn't previously gone.

My issue was resolved when I noticed that I had loaded what appeared to be 2 printer assistance apps - seen in my system preferences. I had a app called 'handyPrint' and also loaded Printopia for AirPrint use. I trust the Printopia app which I had 'purchased' more than the handyPrint that I believe was a freebie. So went into my /Users/USER/Library/PreferencePanes and deleted by way of terminal session. 'rm - rf handyPrint.prefpane'

The system settled down straight away but I did a restart to confirm. Yay! I'm happy now. Back to normal. System typical usage of less than 10%.

This issue is probably particular to my situation, but if it helps point anyone else resolve an issue. Bonus.

On maverics i got the high ram usage of safari webcontent problem

(i had the same on chrome before going to safari)

after reading this thread i deleted library/google

now it seems to work fine

Deleting the folder Library > Google worked for me.  Went from 100% to 2%  

Which Google-folder in Library?

There's one straight under "Library" and one under "Library -  Application Support".

I confirm clearing the reading list, removing all website data and restarting Safari solved the problem for me.

Same problem with Safari here. Trusteer was the culprit but could not disable it from preferences as it did not appear. Had to download the Trusteer installation file and use the uninstall option.

Uninstalling Trusteer Rapport fixed this issue on my Mid 2011 Mac Mini

It was the top level Library > Google folder.

I too found that turning off al extensions etc did not solve the problem  Removing Trusteer Rapport however has solved Safari's CPU hogging issues for now.

I am going to be monitoring the situation for a while as I have just re-enabled Trusteer.  So far the CPU usage is normal, but I can see that rapportd is not responding currently.  So it may hog once again if it starts resonding.

Stuart,

Your answer resolved something that had been driving me nuts: when idle for a while, Safari web content would start downloading something at about 50kbps, giving fears of some kind of malware.

I think I had a couple of spurious entries in the reading list. Deleted them - problem gone.

hey guys... been having issues with safari... since... well... forever.

its slow as MOFO after a while.

i run all the purge stuff... the resetting safari... etc.

i use no extensions and have java off.

i noticed its slow as MOFO with FLASH.

in fact sites that have any flash or heavy graphics tend to bring out the spinning beach ball of doom.

i have a 17 inch... 2.6 with 8 gigs of ram and a 500 ssd HD... this thing was like $4k when new.

shouldn't have issues with performance.... its a beast and i run a lot of video and graphics stuff with it.

my active memory was like 300mb.... when i shut safari off, it'd go to 3-4GIGS

so something is wrong.

I read every response in the 16 pages of this thread.

the thing that worked for me INSTANTLY, was installing Ghostery on the browser.

No clue why or how... but i've checked a few times and it's removed the issue.

just checked again... 3.72 gigs avail. with safari open.

try it, see if it works for ya. :-)