Erlang misc

Erlang/OTP document

If a third instance of the module is loaded, the code server will remove (purge) the old code and any processes lingering in it will be terminated. Then the third instance becomes 'current' and the previously current code becomes 'old'.

即 Erlang 只能保留两个版本的 Code ，如果有第三个版本的 Code ，那么第一个版本的 Code 将被清除，并且基于第一个版本运行的 process 也将被中止。

http://www.erlang.org/ml-archive/erlang-questions/200104/msg00072.html

A process is allowed to run until it pauses to wait for input (a
message from some other process) or until it has executed 1000
reductions.