LION SO SLOW on MacBook Pro that was installed on top of Snow Leopard...Makes my I7 processor look like a G5 PPC, RIDICULOUS!
I spent an hour on the phone with Apple and this helped get some performance back:
This is written out so hopefully anyone can perform this procedure and I strongly recommend you do a BACKUP first.:
1. do a shutdown
2. Hold down ctrl option shift then power button for 1 second
3. Restart when you hear gong hold down shift hold until loading bar
Now in safe mode only OS is running
4. Run disk utility from applications/utilities folder
5. Select Macintosh HD from list on the left
6. Press "Repair disk permissions". Can take about 10 minutes
7. After that finishes run repair disk
8. From the top bar on your mac desktop select Go - computer - Macintosh HD/ library /caches /
9. Select all files in CACHES by typing CMD A
10. After you see them all highlighted DRAG THEM ALL TO THE TRASH
11. Same as 11. Go - computer - Macintosh HD - system - library - caches
12. Select all files in CACHES by typing CMD A
13.. After you see them all highlighted DRAG THEM ALL TO THE TRASH
14. Now same thng for users CACHE folder:Select GO while holding down the OPTION KEY and you'll see LIBRARY as a choice, select it.
15.throw cache folder in trash
16. Go to system preferences-Users groups -login items select - to remove apps that auto start
17. Shutdown
18. Now we will be zapping PRAM/SMC by holding down the following 4 keys on powering up Mac:
CMD-Option-P and R keys until hear startup gong twice
19. Now we rebuild the caches by loading the 5 most used apps (Browsr, Word, etc...) one at a time and quitting app after they load.
20. If its still slow & you see spinning ball etc. do next:
GO Macintosh HD
Open Library
Open startup items. Delete all. (any Apps that auto started on boot up will no longer start automatically)
Open library/ launchAgents delete all
Open library/ launchDaemons delete all
GO and hold down Option key
Select Library (this goes to users individual library )
SOME APPLICATIONS will NEED TO BE REINSTALLED LIKE THE FOLLOWING I EXPERIENCED:
PARALLELS 5 had to be upgraded to version 7
AVID MEDIA COMPOSER 6.0
LIGHTROOM 2 incompatible had to upgrade to version 3
IPhoto 9.x need to upgrade, very slow, especially with RAW files.
HOPE THIS HELPS SOME OF YOU...