Peter. I did some webbench tests to try to reproduce the problem, and
I found two limitations that might have something to do with it. I
would like you to check these two things while your machine is not responding
to apache requests.
If it turns out to be one of these two things, I don't think your issue is
related to the firefox or opera issue.
You could be:
(1) Running out of sockets.
(2) Running out of tcp ports.
(1) Running out of sockets. Any server that accepts connections will wind
up with the socket in a TIME_WAIT state for 2 minutes after the connection
closes.
If your kern.ipc.maxsockets is, say, 5000, then 5000 / 120 seconds ==
only 33 connections per second before you run out of sockets.
(2) Running out of tcp ports. If you are getting a lot of connections from
the SAME IP address, the originating machine (the client you were using
to test connections to your ftp server in this case) may run out of TCP
ports or may start reusing ports that are still in TIME_WAIT on the
target machine.
2 minutes to timeout it would only take 33 connections per second to run
out of ports. But ONLY if all the connections are coming from the same IP
address (since the limitation is based on the {ipaddress,port} tuple, not
just the {port}).
How do you tell? When you hit this situation, do this:
sysctl net.inet.ip.portrange
sysctl kern.ipc.maxsockets
netstat -tn | wc -l
netstat -tn | fgrep TIME_WAIT | wc -l
netstat -m
And that should tell you (and us) what is going on.
If that turns out to be the case, then it probably is not related to the
Opera/FireFox delay issue.
-Matt