Lion is super slow! Should I reinstall?

Question

Hi,
I have a 13” MacBook Pro that has a 2.7GHz i7 processor and 4GB of RAM. I bought this June at it came pre-installed with OS X Snow Leopard. In July, I upgraded to Lion and initially, my computer just had the spinning beach ball a lot more, but a day or two later, my computer seemed like it was running as normal (I’m assuming this was due to Spotlight indexing everything).
However, of late I’ve noticed my computer is SUPER slow! I first noticed the lag in processing speed when it took five minutes to transfer 1GB to a USB flash drive. (I then transferred the files to a Windows PC and back onto the same flash drive and the entire process occurred in under a minute).It takes over two minutes to start up and anywhere between ten seconds to a minute to open a regular application (i.e. iTunes, iPhoto, Firefox, etc). And my laptop heats up a lot faster these days too!
I’ve looked around the discussion forum and tried all the suggested solutions i.e. resetting the PRAM and the SMC, verifying and repairing the disk/permissions (including the one where you have to go through the recovery partition). But nothing has helped. If anything, it's getting worse! Every time I open disk utility now it says it’ll take 4 hours to verify the disk permissions! AHHH. And it’s not like my laptop is filled with useless files, either; my hard drive capacity is 500GB and it still has 372.7GB available. Oh, and I don’t have a virus either because I’ve run the Sophos anti-virus scan three times.
Normally, I’d have taken my laptop to the Apple Store and asked them to figure it out, but I’m currently in the Philippines and they only have Apple Resellers and fake Apple Stores here. I realise it sounds ridiculous but I’m deathly afraid they are either going to kill my MBP altogether or steal my parts.
I was wondering should I completely re-install Lion? If so, how exactly would I go about doing that? I do have a Time Machine back-up of everything on my 1TB external drive, but I don’t have any back-ups prior to getting Lion because I purchased my external later. Also, if I were to re-install Lion and restore from my Time Machine back-up would all my applications still work? I have Microsoft Office 201, Adobe Pro, Photoshop, etc. and if they get uninstalled, I don’t have any of my installation CDs here!
I’d appreciate any help! If you have any ideas, comments, suggestions, anything – shoot me a response. Thank you!

Answer 1

Try to find out what is causing the loss of performance by starting the "Activity Monitor" (from Applications -> Utilities) and sort the processes according to real memory usage or CPU time by clicking at the column headers.
Also have a look at the free Disk space.
According to Apple the minimum hardware requirements for Lion are 2GB of RAM, but I found that not to be sufficient with the Applications I like to be running at the same time. For my workflow I needed 4 GB RAM when on SL, and with Lion I needed 8GB of RAM. The Activity monitor will tell you if you need to upgrade your RAM.
The second bottleneck with Lion is free disk space. Lion will run much more smoothly if you keep a least 10% (and a minimum of 20 GB) of your disk free.
If you find that you do need more RAM, but don't want to upgrade right now, look at the "Activity monitor" to find out which of your processes are fighting for memory and try to avoid running those together at the same time. I found that quite often Safari was eating the available memory and quitting Safari when I did not really need it did help a lot.
Regards
Léonie
P.S. There are quite a few threads in this forum discussing this. Search for "Lion slow"