Dear All, Thanks for your suggestions. It seems there were some upstream problems (resulting in packet loss) which we are trying to iron out with our satellite communications provider. I still think there is something suspicious about these service times, but I will have to wait a few days for this other issue to be resolved before I investigate further. I'll post again later when I have had a chance to try your suggestions. For Henrik & Chris who were concerned about DNS times - yes we have a second DNS server sitting right next to the cache server. I made sure that the DNS server had plenty of in-memory cache available so that it would respond quickly to the second DNS request from SQUID. I thought that I could disable the Squid DNS lookup completely if it proved too slow (if that is possible?). At the moment this is not an issue. Michael - are you saying that I can expect service times of 3-4 Round-Trip-Time even in the best situations - something like 2 seconds? And that this is simply the way that HTTP works (and therefore unavoidable)? Apart from tinkering with TCP window sizes (which I will certainly look into), is there anything else I can do to improve this? Many thanks, Ben. -----Original Message----- From: Henrik Nordstrom [mailto:henrik@xxxxxxxxxxxxxxxxxxx] Sent: 18 June 2006 00:43 To: Chris Robertson Cc: squid-users@xxxxxxxxxxxxxxx Subject: Re: 4 second Cache Miss Service Times fre 2006-06-16 klockan 12:43 -0800 skrev Chris Robertson: > Perhaps the time required to make DNS queries is being included in the > Cache Miss and Near Hits time due to using WCCP (my clients are set > explicitly to use the proxy). Yes DNS time is included in the service time. The service time is measured from where Squid has read the request until it has finished sending the response. But this does not exaplain the differences (see below). Squid always queries DNS for the host name, but only once/twice (it caches the result internally). When using WCCP the DNS service times should be a little better as the client has just made the same DNS query and the result should be cached in your central DNS, assuming both Squid and the client is using the same DNS server (directly, or via DNS forwarder). Regards Henrik
