concurrent connections

I want to test the limit on number of concurrent connections Squid can
handle.

I am using RedHat Linux 6.1 kernel 2.2.12 and Squid 2.3 Stable2. I followed
the
instruction on Henrik Nordstrom' page http://squid.sourceforge.net/hno/ to
raise the limit on file descriptors to 4096, and I can see in cache.log,
there are
4096 file descriptors available. In squid.conf, I set pconn_timeout to 1200
seconds
(keep all the connections persistant). I drive 2000 users sending request to
Squid.
When the number of users is below 1000, everything is fine. But when the
number of
users is more than 1000, a lot of connections is closed. Using 'netstat', I
observered that
number of connections established bounced between 1 and about 950. When more
user send request, number of connections established grows from 1 to 950, but
once
it reaches around 950, it goes back to 1.

Are there any factors other than file descriptors which put a limit on number
of connections?
Maybe there are some limit in OS?

Thanks,
Jenny
Received on Fri May 12 2000 - 11:46:07 MDT