Eclipse cvs I/O has been interrupted.

Error: I/O has been interrupted.
      Error: The most likely cause of the interrupt is either an intermittent network failure or a communications timeout.
      Error: The CVS communications timeout can be adjusted in the Team/CVS preferences.
      Error: Another possible cause is the improper configuration of the "ext" connection method.
      Error: The "ext" connection method can be configured on the Team/CVS/EXT Connection Method preference page 

解决方案：
Window — Preferences — Team — CVS 的 Connection 选项卡，Connection times (s)  设置适当的秒数就好了， 似乎初始值是60，我调到了250，还不行再大些。