Re: What does TCP_REFRESH_HIT resp. TCP_REFRESH_MISS mean?

From: Christian Balzer <>
Date: Wed, 11 Dec 1996 14:51:58 +0100 (MET)

Guillaume Pierre wrote:
>> While analysing the access.log-files of squid 1.1.betaxx I often found
>> the codes TCP_REFRESH_HIT and TCP_REFRESH_MISS. I think I do know what a
>> TCP_REFRESH is, but I do not know the exact meaning of a TCP_REFRESH_HIT
>> and TCP_REFRESH_MISS. I thought a TCP_REFRESH occurs if a user forced a
>> refresh ("reload"). Then the "Pragma: no-cache" header is sent by the
>> client. So when do I get a HIT or a MISS and what does squid do in both
>> cases?
>I think the difference is the following :
>- TCP_REFRESH_HIT : the client sent a request containing «Pragma:
> no-cache». The cache had a copy of the document in its directory,
> and sent an if-modified-since request to the server. Then it got a
> response from the server stating that its version of the object was
> up-to-date.
Nope, that's not due to a client, in this case squid did issue an
IMS request because of the local refresh rules (the client version
would be a TCP_IMS_HIT).
What you mean is a TCP_CLIENT_REFRESH and unfortunately there's no
(optional) way to stop these from reloading the data from the source
no matter what...

>- TCP-REFRESH_MISS : the client sent a request containing «Pragma:
> no-cache». The cache either didn't have a copy of the requested
> document, or had a out-of date one.
No pragma here either, just a failed IMS check, same situation as

>I would be very interested if someone confirmed my explanations. It
>would also be nice if there was a *complete* list of status codes in a
>later version of Squid (or even in the Web server).
Yeah, that would be nice. But I guess it won't happen unless some
folks go and start making documentation w/o waiting for Duane who
has other responsibilities...



  // <CB> aka Christian Balzer, Tannenstr. 23c, D-64342 Seeheim, Germany
\X/ | Voice: +49 6257 83036, Fax/Data: +49 6257 83037
SWB  - The Software Brewery - | Team H, Germany HQ | Anime no Otaku
Received on Wed Dec 11 1996 - 06:00:25 MST

This archive was generated by hypermail pre-2.1.9 : Tue Dec 09 2003 - 16:33:51 MST