Why does my MacBook lock up while my external USB hard drive spins up? It comes right back after a click or two post spin-up. It's pretty annoying since finder often sniffs the drives but the USB drive is typically asleep since I use it mostly for backups.
Notes:
-
The clicking I refer to post spin-up is just a couple of head seeks. The external drive is new and I have several others that cause the same temporary freeze of the OS.
-
The hard drive works great, it goes to sleep because I have the OS configured to allow it to sleep when unused
-
I'd rather not plug and unplug the drive a few times a day (I use it for mostly but not
exclusively backups) -
I don't want the drive spinning all day.. it's usually idle and should be quietly sleeping awaiting work
The issue is I'm sure as Tom suggests that the OS is doing a synchronous I/O touch on every disk… am I expecting to much of a modern OS ? It's lame that any time I open a Finder window it freezes a ton of things for a few seconds… what happened to multi-tasking?
==Update==
This was fixed in a later release of OSX. The system no longer experiences any freezing nor hiccups. I am still using the same external drive as my primary time-machine destination and haven't seen the freeze nor hiccups in ages. Closing the question.
Best Answer
It locks up because it is waiting for a synchronous I/O request to finish, that request takes longer because your hard drive appears to be in not working smoothly, indicated by the clicks you hear.
Three options to remedy the problem:
Find a way to keep the drive from spinning down. A scheduled write, perhaps? Or an option?
Disconnect the drive and use it only when you need it for a manual back-up.
Get yourself a new drive, because it doesn't sound safe to put back-ups on such drive...