问git推给git：'repack‘不是git命令

EN

$ GIT_TRACE=2 git push
trace: built-in: git 'push'
trace: run_command: 'ssh' 'gitserver' 'git-receive-pack '\''~/git/test'\'''
trace: run_command: 'pack-objects' '--all-progress-implied' '--revs' '--stdout' '--thin' '--delta-base-offset'
trace: exec: 'git' 'pack-objects' '--all-progress-implied' '--revs' '--stdout' '--thin' '--delta-base-offset'
trace: built-in: git 'pack-objects' '--all-progress-implied' '--revs' '--stdout' '--thin' '--delta-base-offset'
Counting objects: 7, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (6/6), done.
Writing objects: 100% (6/6), 598 bytes, done.
Total 6 (delta 3), reused 0 (delta 0)
Auto packing the repository for optimum performance.
git: 'repack' is not a git command. See 'git --help'.
error: failed to run repack
To gitserver:~/git/test
   ad2b6ed..2a31eea  master -> master

$ GIT_TRACE=2 git gc
trace: built-in: git 'gc'
trace: run_command: 'pack-refs' '--all' '--prune'
trace: exec: 'git' 'pack-refs' '--all' '--prune'
trace: built-in: git 'pack-refs' '--all' '--prune'
trace: run_command: 'reflog' 'expire' '--all'
trace: exec: 'git' 'reflog' 'expire' '--all'
trace: built-in: git 'reflog' 'expire' '--all'
trace: run_command: 'repack' '-d' '-l' '-A'
trace: exec: 'git' 'repack' '-d' '-l' '-A'
trace: exec: 'git-repack' '-d' '-l' '-A'
trace: run_command: 'git-repack' '-d' '-l' '-A'
...

$ git --version
git version 1.7.0.4
$ uname -a