Combo 10.7.4 Update slowing down and freezing applications
After updating from Combo Mac OS X 10.7.3 to Combo Mac OS X 10.7.4, my third party applications slow to a crawl and freeze on a rotating basis.
Affected applications:
- BOINC with which I do volunteer medical research (3 CPUs used 100% of the time);
- aMule 2.3.1 to download files;
- Mozilla Firefox 12.0 to browse the internet.
I tried to reduce the CPU usage of BOINC (3 CPUs used 80% of the time instead of 100%) to no avail.
I re-installed with some difficulty Mac OS X 10.7.1 from the copy I bought on the Mac App Store to preserve the work I had done on my iMac since the last TimeMachine back-up, but did not improve performance, possibly because I ended up with a mixed system of Mac OS X 10.7.4 components surviving the Mac OS X 10.7.1 re-install.
I am currently performing a TimeMachine re-install of my previous system (Combo Mac OS X 10.7.3) which will take almost a full day and erase my Macintosh HD to copy the TimeMachine content.
When reading posts on AppleInsider.com and TonyMac x86 blog @ http://tonymacx86.blogspot.ca, I came up with at least 3 different explanations:
- The Mac OS X 10.7.4 System takes up all the RAM memory and gives back unused, free memory only slowly, so that third party applications (and Apple applications such as the Finder and Force Quit) don't have enough free memory and freeze on an alternate basis, although my Core i5 quad-core iMac has 12 GB of installed RAM recognized by Mac OS X;
- Apple has changed kext files in anticipation of the upcoming Mac OS X 10.8 Mountain Lion and accidently changed the CPU multiplier so that the CPU is artificially limited to 1.6 GHz (instead of a quad-core 2.66 GHz);
- Apple has changed the /Extra/org.chameleon.Boot.plist file and the following lines of the booting sequence:
<key>GeneratePStates</key>
<string>Yes</string>
should be replaced by using TextEdit to copy the following lines:
<key>DropSSDT</key>
<string>Yes</string>
For more info, see:
http://www.tonymacx86.com/viewtopic.php?f=168&t=59889
I'm just an average user with no programming skills. I don't feel comfortable with doing undocumented tweaks when I don't really understand what I am doing. On this one, I sure hope that Apple engineers are investigating the issue to come up with a fix.
In the mean time, I am using TimeMachine to re-install my previous system (Combo Mac OS X 10.7.3) which will take almost a full day. I have been deprived of my iMac for 3 days and that's all the time that I can spend on a malfunctioning Combo Mac OS X 10.7.4 Update.
quad-core Core i5-750 @ 2.66 GHz
12 GB SO-DIMM RAM
2 TB hard drive with 100 GB of free space
iMac, Mac OS X (10.7.3), Late 2009 Quad-core Core i5 iMac