Periodically Time Machine verifies sparsebundle backups with fsck_hfs. When the sparsebundle is on a Time Capsule (TC) it does this by creating a partial and much smaller representation of the sparsebundle on the TC, transferring the result to the Mac into
and then running
fsck_hfs on it locally (it mounts the local sparsebundle as can be seen with
The problem is that it takes a very long time for
fsck_hfs to verify this representation of very large TC sparsebundles (e.g. >24hrs).
[This leaves the
timemachine process showing in the menu as if it was stuck 'verifying' with the real Time Capsule disk apparently no longer mounted under
/Volumes - which confuses many into thinking the process has died]
fsck_hfs is launched by its parent process
backupd with the parameters
-f -n -x -E. There are various posts about
fsck_hfs working much more efficiently if allowed to use more memory (
-c option). By default (at least on my system) it seems to be limited to 3Gb.
My question is, is there any way to pass a config that might cause
backupd to launch
fsck_hfs with the additional (
-c) parameter and so run faster?