[distcc] More requests than distccd's?

[Martin Pool]

On Wed, 15 Sep 2004 12:59:45 -0700 (PDT), Victor Norman
<vtnpgh at yahoo.com> wrote:

> So, another way of asking this question is, "What happens if you oversubscribe
> your compilation servers?"

The clients will try to open sockets to the servers.  Since the
servers only accept a limited number of connections[0] the rest of the
clients will block waiting to connect.  Normally they will be held in
the 'accept queue' on the server, so the TCP socket connect is open
but not flowing.  Once some of the current jobs finished, new clients
will be accepted -- probably in the order they arrived, though that
depends on the server OS.  If this process takes too long, the client
may timeout, run the job locally, and then it will not use that server
for a while.

So the net effect is that servers should not be overloaded beyond the
limit imposed by the server, but scheduling can be quite nonoptimal
when you have multiple active clients.

-- 
Martin