I am running a POE server that handles multiple clients, each with a
long-lived TCP/IP connection. A client will send at least one request
and get a reply, and can optionally send additional requests. The
client can reconenct if the server hangs up the conenction between
requests. The server keeps a client connection alive for two minutes
after the last request has been handled, and then shuts it down.
At the beginning of handling a client request:
$kernel->alarm_remove($heap->{AlarmId}) if (defined $heap->{AlarmId});
At the end of a client request, after put(response):
$heap->{AlarmId} = $kernel->delay_set('timeout', 120);
In the alarm event handler:
$_[KERNEL]->yield("shutdown")
This is working fine. However, in some cases, my server gets a flood of
client requests, where it would survive fine without the time-out,
but runs out of file descriptors with the keep-alive timeout.
What I would like to do is catch the condition that I am getting close
to running out of file descriptors, and then close all those client fds
that are idle. I realize I'll have to keep a data structure of idle
client connections; what I don't know is how to properly hook into POE
to count the number of current open fds (across all ports that POE
listens to). Where and how can I cleanly do this? I can hook into the
'Acceptor' of the POE::Component::Server::TCP class, but don't see a
corresponding callback to track all connection close events. ANd it
would be nice not to have to count fds myself :-)
Cheers, Hildo
