git pull 或者执行一些其他git操作 Auto packing the repository for optimum performance. You may also run "git gc

有时候当你运行一些git命令（比如git pull）的时候，会有如下提示：

Auto packing the repository for optimum performance. You may also
run "git gc" manually. See "git help gc" for more information.

翻译：

自动包装最佳性能的存储库。
你也可以手动运行 ‘get gc’ 。有关更多信息,请参见“git帮助gc”。

当有这个提示的时候，直接运行 ’ git gc ‘，就可以了。

原因：

Git 往磁盘保存对象时默认使用的格式叫松散对象 (loose object) 格式。Git 时不时地将这些对象打包至一个叫 packfile 的二进制文件以节省空间并提高效率。当仓库中有太多的松散对象则就会提示你运行 ’ git gc ‘。

我们可以运行 ’ find .git/objects -type f ’ 命令，查看一下 objects 目录里有多少对象，如下：

$ find .git/objects -type f
.git/objects/07/0cc4950ddcd2595a8134d8e560aef2a733e581
.git/objects/13/93d47387301d83214a34883f182cacb717762c
.git/objects/1c/1962af2351551af106a46a2bf43543a8bacf52
.git/objects/1c/4c0087a2c81ae4d1a521eddcecbbedc5c90270
.git/objects/36/39f696bdc97385fefb67926cdc0895e3dc5bb3
.git/objects/48/ec12b8a1a0d53d49e80156cfe969e438384da1
.git/objects/52/65597ee5edea6bc415506f097ebe072ef79363
.git/objects/52/86195cdb9c73333e06fb755272030105c50ef3
...
.git/objects/pack/pack-0c73db178d8a396a3ab624b4acf9dda479593691.idx
.git/objects/pack/pack-0c73db178d8a396a3ab624b4acf9dda479593691.pack
.git/objects/pack/pack-7c6c1af87ebb721211b490eec0ee6d5b49b5b280.idx
.git/objects/pack/pack-7c6c1af87ebb721211b490eec0ee6d5b49b5b280.pack

然后在运行 ’ git gc ’ 命令后，在执行刚才的命令，看下 object 目录里面还剩下多少对象，如下：

$ git gc
Counting objects: 11099, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (3219/3219), done.
Writing objects: 100% (11099/11099), done.
Total 11099 (delta 7805), reused 10988 (delta 7712)

userName@DST56034 /D/gitProject(master)
$ find .git/objects -type f
.git/objects/info/packs
.git/objects/pack/pack-1ddf288322e0efcb6ca533b685b707ef269ff8f0.idx
.git/objects/pack/pack-1ddf288322e0efcb6ca533b685b707ef269ff8f0.pack