[squid-users] Uneven load distribution between SMP Workers

Good Afternoon Everyone

I'm running Squid 3.3.5 on 3 multicore systems here, using SMP and 6
workers per server dedicated to their own core. Each one running OS
RHEL6 U4 with 2.6.32 kernel.

I'm noticing as time goes on, some workers seem to be favoured and
doing the majority of the work. I've read the article regarding SMP
Scaling here:

http://wiki.squid-cache.org/Features/SmpScale

However I'm find our workers CPU time is differing quite substantially;

Server 1:

TIME+ COMMAND
287:01.16 (squid-3) -f /etc/squid/squid.conf
248:36.07 (squid-2) -f /etc/squid/squid.conf
146:04.90 (squid-5) -f /etc/squid/squid.conf
140:59.06 (squid-1) -f /etc/squid/squid.conf
111:24.22 (squid-6) -f /etc/squid/squid.conf
120:41.21 (squid-4) -f /etc/squid/squid.conf

Server 2:

TIME+ COMMAND
618:05.08 (squid-1) -f /etc/squid/squid.conf
405:59.84 (squid-5) -f /etc/squid/squid.conf
362:29.37 (squid-3) -f /etc/squid/squid.conf
318:56.54 (squid-2) -f /etc/squid/squid.conf
211:11.80 (squid-6) -f /etc/squid/squid.conf
204:48.51 (squid-4) -f /etc/squid/squid.conf

Server 3:

TIME+ COMMAND
497:21.70 (squid-5) -f /etc/squid/squid.conf
389:32.63 (squid-1) -f /etc/squid/squid.conf
171:31.28 (squid-6) -f /etc/squid/squid.conf
177:15.38 (squid-4) -f /etc/squid/squid.conf
346:28.21 (squid-3) -f /etc/squid/squid.conf
174:05.69 (squid-2) -f /etc/squid/squid.conf

I can also see the connections differ massively between the workers:

Server 1:

(Client and Server side connections)

squid-1 145 ESTABLISHED
squid-2 547 ESTABLISHED
squid-3 929 ESTABLISHED
squid-4 118 ESTABLISHED
squid-5 298 ESTABLISHED
squid-6 276 ESTABLISHED

Server 2:

(Client and Server side connections)

squid-1 899 ESTABLISHED
squid-2 215 ESTABLISHED
squid-3 311 ESTABLISHED
squid-4 96 ESTABLISHED
squid-5 516 ESTABLISHED
squid-6 70 ESTABLISHED

Server 3:

(Client and Server side connections)
squid-1 517 ESTABLISHED
squid-2 96 ESTABLISHED
squid-3 366 ESTABLISHED
squid-4 83 ESTABLISHED
squid-5 1030 ESTABLISHED
squid-6 189 ESTABLISHED

I'm a little concerned that the more people I migrate to this solution
the more the first 1 or 2 workers will become saturated. Do the
workers happen to have some form of source or destination persistance
for (SSL?) connections or something that might be causing this to
occur?

And is there anything I can do to improve the distribution between
workers? Or have I missed something along the line?

Cheers
Received on Tue Jul 30 2013 - 12:44:47 MDT