when to add a process [and plug for Erlang Workshop]

[Hal Snyder]

This is a note to indicate how much I enjoyed the Erlang Workshop at
Snowbird last week. It was great to meet Erlang experts, learn of new
developments, and exchange ideas.

Just a few examples: HiPE on AMD64, Joe's EX11 GUI, a demo of the
Dialyzer catching errors in Erlang code, and the SSH2 protocol in
Erlang.


Jay Nelson's talk, "Structured Programming Using Processes", made me
wonder - when is it a good idea to create a new Erlang process?
Here are a couple cases:

1. Tracking state - any state machine, whether coded with the OTP
behavior or not. Protocol drivers are classic examples. Another
example is tracking which of several external redundant resources is
to be used in a high availability setting. (Of course everything is an
fsm at some level, but there is a practical principle here as well.)

2. Serializing access to a resource.

3. Monitoring an external Unix process (Erlang port).