Periodic disk activity when idle

Question

Mac-1984 Author

Level 1

30 points

Periodic disk activity when idle

Hi,

I've recently purchased a new Macbook Pro. Whenever my machine is idle, I can hear some disk activity every 30 seconds, even without any applications launched. Activity Monitor confirms this disk activity: every 30 seconds or so, I see red spikes appearing: it's almost like clockwork!

Is anyone else having this issue? I'm worried that this might crash my hard drive :S Thanks in advance! 🙂

Macbook Pro (2010), iPhone 3G, Mac OS X (10.6.4)

Posted on Sep 26, 2010 4:30 AM

Reply

Answer 1

WZZZ

Level 6

13,238 points

Sep 26, 2010 6:16 AM in response to Mac-1984

Try a PRAM reset. Hold down CMD-Option-P-R at the startup chime. Wait for two more chimes, total three.

http://discussions.apple.com/thread.jspa?threadID=2574566&tstart=2

Reply

Answer 2

Mac-1984 Author

Level 1

30 points

Sep 26, 2010 8:52 AM in response to WZZZ

I tried it but it doesn't seem to work :S I still get spikes of disk activity.

Reply

Answer 3

WZZZ

Level 6

13,238 points

Sep 26, 2010 9:53 AM in response to Mac-1984

Can you see what it is in Activity Monitor?

Reply

Answer 4

Mac-1984 Author

Level 1

30 points

Sep 26, 2010 11:20 AM in response to WZZZ

I can't see what process it is in Activity Monitor. But I ran fs_usage in Terminal and found that the launchd process is responsible for the writes. The process appears to sync its cache to the drive and has something to do with DKIOCSYNCHRONIZECACHE. I've searched on Google and found someone with what seems to be the exact same problem, including the fs_usage results: http://discussions.info.apple.com/thread.jspa?threadID=2540530&tstart=75.

It looks like every 30 secs, the machine is trying to sync the cache with the harddrive. From what I've experienced, it only writes to the harddrive when the cache doesn't match with what's on the harddrive: hence why sometimes, it can take 1 minute of 1.5 minute (multiples of 30 seconds) to write again.

Basically, something is updating my cache. I just can seem to figure out what that is.

Reply

Answer 5

WZZZ

Level 6

13,238 points

Sep 26, 2010 1:03 PM in response to Mac-1984

In that link, I see mds all over those entries. Just guessing, but could this be related to Spotlight sporadically trying to index the drive and getting hung up? What about forcing Spotlight to reindex the drive by dragging the HD icon into Spotlight> Privacy for a bit and then removing it.

Or, maybe just voodoo, but try trashing the spotlight.plist files in your user.

Have you tried a restart?

EDIT or, even simpler, just leave the Volume in Privacy for a while and see if the disk activity stops.

Other than that, this stuff is way over my head.

Message was edited by: WZZZ

Reply

Answer 6

Mac-1984 Author

Level 1

30 points

Sep 27, 2010 10:47 AM in response to WZZZ

I've turned off spotlight and reindexed like you said but it doesn't help. I even started in safe mode and the problem persists. Thanks for the help man, but I'm thinking its just better to go back to the store and let "experts" look at the problem. My computer is only 7 days old...:(

Reply

Answer 7

Mac-1984 Author

Level 1

30 points

Sep 27, 2010 10:52 AM in response to Mac-1984

Btw, I found some more people having a similar problem. Noone seems to have found a solution though...
http://discussions.apple.com/thread.jspa?threadID=2215418
http://hintsforums.macworld.com/archive/index.php/t-77776.html

Reply

Answer 8

Oct 29, 2010 9:51 PM in response to Mac-1984

I recently got a Mac Pro 8-core (Intel Xeon), and have been experiencing constant hard drive activity, but not from the beginning, so it had to come from something I installed.

First off I connected my laptop via firewire and ran Disk Warrior. There were acute problems, as part of the DW conclusion text was in red. After repair, and restart, I found that the the disc activity continued. I saw this thread and the link to another thread prompted me to uninstall Adobe CS3. That did the trick. After a reboot, I ran the CS5 Cleaner program, but that didn't seem to find anything after the uninstall. All that remained was to delete the cache.db in /Library/Application Support/Adobe/Adobe PCD/cache/. I rebooted again for good measure. Voila! No more disc activity. I think I'll try re-installing Adobe CS one program at a time, and not do them all in one install. That way, if the disc activity starts up again, I'll know which program did it. Hopefully, that won't happen, and all the demons are exorcised from this machine.

Reply