"git commit" of single file takes 5 minutes, mounted fileystem/diskimage with 50G GIT repo + 900G of builds articles

Based on a previous thread “First Git status takes 40+ minutes, when mounting fileystem/diskimage with 50G GIT repo + 900G of builds articles”

The context is that 
  1. git wokspace was clone(50G)
  2. some 30 platorms build(900G)
  3. This tree was then copied into a new diskimage/filesystem + git update-index --refresh" was done to update the index to the new filesystem, then frozen.
  4. New workspaces created by cloning this frozen diskimage(< 30 seconds)
  5. This diskimage was mounted on a new machine
  6. A file was modified and "git add/commit" was done

I have done “git update-index –refresh”, in the mounted filesystem, as above This has improved “git status/diff” timing from 40+ minutes to 1.5 minutes for the first time and <5 seconds for subsequent calls.

But "git commit -m "dummy commit" of a 1 line change in 1 file takes about 5-6 minutes, everytime in this workspace. Tracing shows a whole bunch. The entire 5-6 minutes worth of the following sort of trace logs. 3:13:50.320930 trace git-lfs: filepathfilter: rejecting "x/y/z.o.command" via [] 13:13:50.320940 trace git-lfs: filepathfilter: accepting " x/y/z.o.command " 13:13:50.320862 trace git-lfs: filepathfilter: rejecting "a/b/c/d.o.command" via [] 13:13:50.320972 trace git-lfs: filepathfilter: accepting " a/b/c/d..o.command"

Does anyone have any insights on what could be causing this?

On the other hand, if I had 
 
Thanks,
Sarvi
Occam’s Razor Rules