Well, I tried it after enabling Trim Enabler 3.3 on my iMac's internal 7200rpm HD. My 845DC EVO SSD is connected via eSATA.
When you are in Disk Utility, you select the formatted disk, not the top-level disk to "repair"
I don't think that matters. These two reports are for the top level followed by the disk image. I put the lines in bold.
Actually, Console did not show much and didn't show Trim nor any other part of
Disk Repair. The following reports are from
Disk Utility:
(Drive - top level)
Verifying and repairing partition map for “Samsung SSD 845DC EVO 960GB Media”
Checking prerequisites
Checking the partition list
Adjusting partition map to fit whole disk as required
Checking for an EFI system partition
Checking the EFI system partition’s size
Checking the EFI system partition’s file system
Checking all HFS data partition loader spaces
Checking booter partitions
Checking booter partition disk1s3
Checking file system
Checking Journaled HFS Plus volume.
Checking extents overflow file.
Checking catalog file.
Checking multi-linked files.
Checking catalog hierarchy.
Checking extended attributes file.
Checking volume bitmap.
Checking volume information.
Trimming unused blocks.
The volume Recovery HD appears to be OK.
Volume repair complete.
Updating boot support partitions for the volume as required.
Reviewing boot support loaders
Checking Core Storage Physical Volume partitions
Updating Windows boot.ini files as required
The partition map appears to be OK
(Disk image)
Verify and Repair volume “845 EVO”
Checking file system
Checking Journaled HFS Plus volume.
Checking extents overflow file.
Checking catalog file.
Checking multi-linked files.
Checking catalog hierarchy.
Checking extended attributes file.
Checking volume bitmap.
Checking volume information.
Trimming unused blocks.
The volume 845 EVO appears to be OK.
Volume repair complete.
Updating boot support partitions for the volume as required.