ra_serf: The server sent a truncated HTTP response body.

ra_serf：服务器发送的HTTP响应体截断。

The data sent is too big and the server closes the connection due to reaching
a limit.

Possible steps which can help fix this issue:

* Increase the timeout value on the server

*
set compression level to zero on the server (will make everything

slower but helps with this issue)

* make sure all proxies that are in between you and the svn server also

have the timeout values increased

以上的这些解决办法实现起来都比较困难，其实只要自己在网速好的时候重新更新就可以。