RE: [squid-users] 304 response preventing site from loading

tor 2010-09-30 klockan 13:24 +1000 skrev Paul Freeman:

> However on further investigation, I don't think this is the case in this
> instance. For some reason, the squid GET request to www.mhhe.com (IP
> 12.26.55.139) takes a long time to be completed - approx. 2 minutes. Some
> data is returned quickly but then there is a period where on my squid server
> I see a TCP Previous Segment lost then squid server sending Dup ACKs to
> www.mhhe.com and www.mhhe.com sending TCP Retransmissions for the same
> segment. The Retransmission RTTs to ACK the one segment are at 0.2,4,8,16,32
> and 60 seconds. After that segment has finally been received, the rest of
> the data is received OK.

This smells like TCP window scaling issues in a firewall somewhere.

Try as a test:

  echo 0 >/proc/sys/net/ipv4/tcp_window_scaling

note that this is somewhat intrusive and reduces performance of TCP in
general, but is an easy way of testing for the problem.

Regards
Henrik
Received on Tue Nov 09 2010 - 22:43:37 MST