今天在检出一个项目时，check out 中断，由于项目文件太多，运行 clean up 命令进程会卡死。然后在 StackOverflow 找到了解决办法，亲测可行：
- Delete the .svn directory for your working copy.
- Start a new checkout in a new, temporary directory.
- Cancel the checkout (we don't want to wait for everything to get pulled down).
- Run a cleanup on this cancelled checkout.
- Now we have a new .svn directory with a clean database (although no/few files)
- Copy this .svn into your old, corrupted working directory.
- Run svn update and it should bring your new partial .svn directory up to speed with your old working directory.