[squid-users] i have problem for first request

Dear all,

I run squid under debian, my when i restart squid or squid -z , my
client has problem with first open facebook.com, it's very slow, but in
the next request is not slow.slow means 45 minutes, i tested myself.
but youtube or other site doesn't has problem in first request.
Even facebook can't open after first request.

--regards