I have severel WD USB drives on my new Mac Mini running Mountain Lion, and recently one of them, a 2tb drive, started making noises it never has before that sound like it’s being accessed hot and heavy and seeking loudly. I’ve never heard any of my WD MyBooks make that kind of noise, scritchy-scratchy-clicky sounds.
Of course I suspected that the drive might be getting ready to fail, so I backed it up, but I can’t figure out what’s making that one drive do that. It’s less than a year old, and I have a 500 gb WD USB drive that still going strong and it’s almost 7 years old. I find it hard to believe that a WD drive would fail in less than a year. The drive has 800gb free on it, so it’s not filled up either.
It will make these sounds for 15-20 minutes, then go silent again for a while before doing it again. I’ve run Disk Utility against it numerous times and it always comes up okay, but that might not really mean anything. I’ve tried changing out the cable, switching it from the hub to the USB port on the Mac, plugging it into a different power outlet, and tried using Terminal to see if I could find out anything about that particular drive in BSD, but I know too little of UNIX to do that.
I tried using iosnoop in Terminal and got a lot of this:
0 1 W 32792 4096 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
0 1 W 43024 8192 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
0 1 W 106960 8192 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
0 1 W 570192 4096 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
0 1 W 571264 4096 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
0 1 W 571272 4096 launchd ??/<unknown (NULL v_parent)>/<unknown (NULL v_name)>
And a lot of this:
dtrace: error on enabled probe ID 4 (ID 1031: io:mach_kernel:buf_strategy:start): invalid user access in action #3 at DIF offset 0
dtrace: error on enabled probe ID 4 (ID 1031: io:mach_kernel:buf_strategy:start): invalid user access in action #3 at DIF offset 0
It’s puzzling that the disk access light isn’t flashing while the drive is making all that noise, when I can see a lot of disk writes happening in Activity Monitor at the time. What’s writing to that disk? I have no idea! What might it be writing? No idea, but the writes are definitely happening big time.
So, it’s this drive getting ready to fail on me? If not, what might be going on with it? Might it have something to do with Mac OS X?
