iMac Snow Leopard thrashing hard drive - how to troubleshoot?

Freakitchen · 30 Jul 2011 at 18:25

Hi guys. Got a bit of a problem with my iMac that I'd appreciate some help with. Not had many problems with this thing so far, so not sure how to proceed!

Basically, despite being an i5 with 4GB of RAM, it's starting to feel a lot slower than my C2D MacBook. The most obvious thing is loading applications, which seems to take an age getting them to a useable state, with frequent beachballing. Once up and running, apps are snappy enough, but while they're starting (and closing for that matter), I can hear the hard drive thrashing constantly (not a click, just a noise I'd associate with constant access that stops as soon as the app is useable).

Are there any steps I can take to try and cure this? I want to upgrade to Lion but am loathe to do it while SL is seemingly having issues, and really don't want to re-install!

Cheers in advance.

steveo · 30 Jul 2011 at 18:34

have you checked to see if your hard drive is one thats been recalled by apple ??? OCUK Linky

cheef · 30 Jul 2011 at 18:51

Looked what's going on at the time of issue in Activity Monitor?

uniQ · 30 Jul 2011 at 18:59

As always run disk utility > repair permissions and verify disk see what it turns up.

Freakitchen · 30 Jul 2011 at 21:20

Thanks uniQ, that seems to have helped a lot. The verify disk showed up no errors, but the permissions repair threw up lots of corrections. Wondering how it got like that in the first place!?

Steveo, thanks, I checked that before, my drive is a WD unit.

MacRS4 · 30 Jul 2011 at 21:44

Can you download and run the AJA System Test utility to get the throughput of your drive?

Also, do you have a Boot Camp partition by any chance?

Freakitchen · 30 Jul 2011 at 22:01

No Boot Camp Partition. I ran the system test at its default settings, a 128MB video file. Came back with a write speed of 70.2MB/s and read of 68.8MB/s

MacRS4 · 30 Jul 2011 at 23:03

That's about right then.

My 2011 iMac's drive performance drops substantially when I have a BC partition on it... Haven't quite got to the bottom of it yet.

uniQ · 31 Jul 2011 at 13:56

When the hard drive is thrashing open Activity Monitor click on the System Memory tab at the bottom and take a look at Page Outs. If your RAM gets used up it starts to page out inactive memory to the hard drive which is much slower than RAM and could cause these symptoms.