0

My second hand 2013 iMac has been running really slowly.

I have already done a complete wipe and reinstall, but that didn't help.

trying to get to the bottom of this, and suspecting imminent HDD failure, I booted from a USB El Capitan installer, then ran diskutil in Terminal, and discovered a whole bunch of additional disk images.

dev/disk0 is the internal physical disk, formatted as GUID journalled, with the EFI partition at 209.7MB, and the main Apple_HFS partition.

dev/disk1 is my USB Flash installer, also with EFI partition of 209.7MB and the main Apple_HFS partition.

dev/disk2 is a GUID disk image (Recovery Partition?), with a 209.7MB EFI partition and a 6.5GB Install ESD partition.

Here's where it gets weird: Disk3 is also a GUID disk image, with a 2 GB Apple_HFS OS X Base System. These four devices show up in the GUI Disk Utility.

Then I have disk4 through disk16, with no type and named "untitled", 7 of which are 524.3 KB (disk5 through disk9 & disk13), 2 are 6.3MB (disk10 & disk16), 1 is 5.2MB (disk4), then 2.1MB disk3), 2 are 1.0MB (disk12 & disk15).

If I do diskutil info /dev/disk'n', I get the following Mount Points:

 /dev/disk4 - Mount Point: /private/var/log
 /dev/disk6 - Mount Point: /private/var/tmp 
 /dev/disk7 - Mount Point: /private/var/run
 /dev/disk8 - Mount Point: /System/Installation
 /dev/disk9 - Mount Point: /private/var/db
 /dev/disk10 - Mount Point: /private/var/folders
 /dev/disk11 - Mount Point: /private/var/root/library
 /dev/disk13 - Mount Point: /Library/Preferences
 /dev/disk14 - Mount Point: /Library/Preferences/SystemConfiguration
 /dev/disk15 - Mount Point: /Library/Keychains
 /dev/disk16 - Mount Point: /private/var/tmp/RecoveryTemp

I tried running fdisk -i -a hfs /dev/disk'n' (where 'n' is the number of the disk I want to remove), but I get "Resource busy" for all of them except dev/disk12, where I got "could not open MBR file /usr/standalone/i386/boot0: No such file or directory"…

I then get: ————————————————————————————————————————————————-- ———- ATTENTION - UPDATING MASTER BOOT RECORD ————- —————————————————————————————————————————————————-

Do you wish to write new MBR and partition table? [n]

How do I get rid of these additional disks?

TIA!

3
  • It sounds like your drive is failing. Removing those directorys really won't help the issue. If you issue the command diskutil info disk0 | grep SMART can you post the output in your quesiton? Have a look at iMac 27" late 2012 SSD upgrade for some good info
    – Allan
    Jul 5, 2016 at 1:08
  • Thanks Allan; will do. The result shows SMART status: Verified, which suggests the drive is healthy… Jul 5, 2016 at 1:23
  • That's true,, but it could be an intermittent failure. Try Disk Drill for a full diagnostic as well. Its free, too
    – Allan
    Jul 5, 2016 at 1:43

1 Answer 1

1

I smell an impending death of a hard drive. For that case, I suggest an upgrade to an SSD will do. Not only you have a newer storage device but also you have a faster computer altogether.

On a side note, if an SSD isn't your fancy, you can always purchase a new HDD, but go for the better models since it will benefit you more in the long run.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .