I've been wrestling with Squid for a large site I'm contracting at right now. I was curious - what version of Squid is WMF running now, and would it be ok if someone sent me the configs so I can see how you have it set up right now?
Is cache peering in use? Are you running Squid 3.0, and COSS or AUFS?
Thanks for any relevant info...
I will feed back anything that seems useful from what I've learned here.