方法有很多種，先說解決了我燃眉之急的。

方法一:

找到.gitconfig，新增如下配置。(或者用git config --global命令)

[core] 
packedGitLimit = 512m 
packedGitWindowSize = 512m 
[pack] 
deltaCacheSize = 2047m 
packSizeLimit = 2047m 
windowMemory = 2047m

方法二：

網上看到做多的，

git config --global core.compression 0

方法三:（stackoverflow上面看到的高分解答）

First, turn off compression:

git config --global core.compression 0

Next, let's do a partial clone to truncate the amount of info coming down:

git clone --depth 1 <repo_URI>

When that works, go into the new directory and retrieve the rest of the clone:

git fetch --unshallow 

or, alternately,

git fetch --depth=2147483647
 

Now, do a regular pull:

git pull --all

I think there is a glitch with msysgit in the 1.8.x versions that exacerbates these symptoms, so another option is to try with an earlier version of git (<= 1.8.3, I think).

這一套三板斧下來，應該可以解決80%人的問題了。