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Safari Web Content high CPU usage

Hi everyone!


Safari become very lag when I open a new tab or pages, and when I checked Activity Monitor, the one that made my mac lag is Safari Web Content, it can eats 80-90% of CPU.However, it only happened if I open new tab/pages. I never experienced lag with other browser such as Firefox before.


Anyone ever experienced this? Any suggestion or solution will be appreciated.


Thanks.

Macbook 13 inch late 2008 model, Mac OS X (10.7)

Posted on Jul 20, 2011 1:10 PM

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264 replies

Nov 6, 2013 1:45 AM in response to solidrocketbooster

I had exactly the same issue!! 100% CPU on Safari Web Content. the site causing it was an oxford university Mirror hosting site.. I reset safari.. nothing. I formatted my HDD and clean installed mavericks. opened safari with just my Apple ID registered... nothing changed! after a minute or 2 it was 100 % again.. spoke to many tech guys and nobody could figure out what it was!


I was sat at my mac this morning making another Install USB for mavericks and decided to clean up my bookmarks and reading list entries..


There it was!! An XBMC download link in my reading list!! Deleted it and PROBLEM IS SOLVED!!


This has done my head in for a few weeks! been using google chrome ever since! ive now deleted it and i hope this can help others figure out the issues with their own machines!!


Hope this helps you guys!!!


Stuart

Aug 15, 2017 6:11 AM in response to scryedz

When I open Safari with my default tabs, I do not get the excessive CPU usage, but as soon as I open another, I get the CPU and fan ramping up. I've found that I can open Activity Monitor, kill safari_web_content, and I get everything returning to normal. In fact my current safari sessions do not appear to be affected by killing the process.

Jul 20, 2011 6:26 PM in response to scryedz

Hi


How much RAM do you have installed on your computer? You ought to max your RAM if you are running Lion due to system and load requirements.


I'm seeing about 2 GB of RAM allocated to Safari Web Content (this is a new process introduced in Safari 5.1). However, I have 12 GB of RAM and an i5 processor on my iMac, so CPU draw is not signficant (about 6 percent).


Seems Apple has split in two the Safari process in 5.1 from the singular process used in earlier versions of Safari. Via Activity Monitor I now see "Safari" and "Safari Web Content".


Not sure exactly what drives the Safari Web Content process, however, large number of tabs open, and/or large number of extensions or plugins will require more RAM and CPU usage. In any event, the activity level and RAM requirements in this process seems excessively high. Perhaps others will add their experience here.

Jul 20, 2011 10:22 PM in response to Hawaiian_Starman

Hi! Thank you for the reply.


I already maxed out the RAM. My macbook can handle up tp 4 GB RAM. Also I noticed, my macbook become very lag if I open certain website, such as in this case Gizmodo.com, the fan ramp out suddenly, and Safari become slow and lag. When I open Gizmodo with Firefox nothing happen, the fan is quiet and everything smooth.

Is there something bad with my Safari, I just upgraded to Lion hoping to eliminate the problem I got when I had Leopard and Snow Leopard, but problem stil persist. 😕

Jul 21, 2011 4:38 AM in response to scryedz

May be a corrupt cache file.


Quit Safari if it is open. Then, go to your Finder and navigate to: Your User Library>Cache>com.Apple.Safari folder> there, move the Cache.db file to the trash. Then, Finder menu>select "secure empty trash". Restart Safari and try Gizmodo.com.


If the fans continue to ramp, try Safari from another User Account (same site). Let us know if you have excessive fan activity in the other account.

Jul 21, 2011 6:45 PM in response to Hawaiian_Starman

What I've noticed is that, over time, the Safari Web Content process eats up more and more RAM. When I first opened Safari just now, Safari Web Content was using ~160 MB of my 4 GB RAM. Now it is up to 327 MB, with 2 windows (each with 2 tabs) open. I restarted Safari because the Safari Web Content process was using over 1.5 GB of RAM, leaving me with only ~ 90 MB free RAM. That was with Safari, Groupwise (email program), Mail, Activity monitor, and Magic Prefs running.

Jul 21, 2011 11:38 PM in response to Hawaiian_Starman

Hi thank you for your suggestion, I've tried what you suggest by deleting Cache.db file, however the problem still persists. I tested Safari on another account by creating a test account, and suprised Safari do very well on test account, it didn't use high CPU process. I am not sure what happen, is it because I've used Safari for long time so it accumulated some junks, or maybe Safari extensions cause any conflict?

Jul 22, 2011 2:22 AM in response to Hawaiian_Starman

I'm seeing the two parts of Safari using over 5GBs of my RAM & it's slowing everything down terribly! Ever since i updated this browser has sucked up all my RAM, and been a huge time & energy waster. Is this supposed to be only for those using LION? If so, why was it included in my Software Update, cause I don't have Lion installed, so it should not have been sent me, no?
I'm so frustrated, cause the previous Safari was finally working better than any I'd used in many years. Any way to revert back?

Jul 22, 2011 3:11 AM in response to scryedz

You're welcome.


If Safari functions as expected in another User Account, then the problem is specific to your regular user account. That would narrow it down to any Safari plug-in or extension unique to the regular User Account.


I suggest focusing on extensions first. If you have one or more extensions installed follow these steps.


Open Safari Preferences>Extensions and disable each extension by clicking on the extension, then unchecking the "enable" box. Then, restart Safari.


If performance improves, then return to Safari Preferences and enable one or two extensions. Restart Safari. If CPU activity is normal, then continue down the list following the above sequence until you find the culprit.


As with any major OS or application update, it's up to the 3rd party developer to bring their product into compliance with new system requirments.

Jul 22, 2011 7:58 AM in response to mbender83

similar situation. I notice safari is taking somewhere close to 2gig of my memory and causing my entire os to be very sluggish. I have even tried to isolate the problem by resetting safari and disable all my extensions to it. It just seems it's the way how Apple have programmed safari to behave. hope they acknowledge the problem and provide a fix soon.

Safari Web Content high CPU usage

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