process pools?

[Joe Armstrong]

Julian Assange wrote:

>Two questions:
>
>        1) ...
>
>
>
>        2) What is the best method to implement worker threads? i.e
>           I'd like a pool of processes (one for each outbound
>           socket), which listen on the same message queue for
>           requests -- the first free process reads gets the
>           message.
>

I suspect you don't need to keep a pool of workers - I'd just spawn off 
a new process for
each new request (possibly limiting the number of processes that can be 
spawned off).

I use tcp_server.erl (appended) for this - this I'm constantly modifying 
(one day I'll get it right)

The call tcp_server:start_raw_server(2000, F/1, 25)
starts a listener on port 2000. The fun F/1 is called every time a new 
connection is setup on
port 2000. At most 25 parallel sessions are allowed.

Read the comments at the start of the file.

F/1 should go into a receive loop where it can receive gen_tcp messages

This should probably do what you want.

/Joe Armstrong

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