Re: Our loner squid retrieiving unreqested mystery data

Henrik Nordstrom writes:
> Marc Lucke wrote:
> >
> > I was wondering why Squid 2.2 stable 4 would go out & get over 300 mb
> > & 100 mb the next day worth of data by itself at full speed without a
> > request for it (byte hit ratios were showing negative).
>
> I too have seen this, but I don't think I have seen it since configuring
> quick_abort and range_offset_limit to be as restrictive as possible:
>
> quick_abort_max 0 KB (16 kb is the default)
> range_offset_limit 0 KB (this is the default)

A few days ago I saw our squid fetching more data than requested by
clients. It was squid 2.2.STABLE3 but the same problem appears with
2.2.STABLE5.

The problem is related to range requests: there are some web servers,
like the geocities' servers, which advertise themselves as supporting
range requests (Accept-Ranges: bytes) but in fact they don't. With
range_offset_limit set to 0 KB squid will fetch the whole file as
given by the server, but will send to the client only the requested
range.

I'm not sure what is the correct fix but I think that when
range_offset_limit is set to zero squid should send the whole file
when the server doesn't reply with a range response. I made a patch
which fixed the problem for us (see bellow).

Radu Greab

--- squid-2.2.STABLE5.orig/src/client_side.c Sun Oct 24 06:21:47 1999
+++ squid-2.2.STABLE5/src/client_side.c Sun Oct 24 07:29:47 1999
@@ -1043,6 +1043,8 @@
         range_err = "canonization failed";
     else if (httpHdrRangeIsComplex(http->request->range))
         range_err = "too complex range header";
+ else if (Config.rangeOffsetLimit <= 0)
+ range_err = "no range in reply and range_offset_limit <= 0";
     /* get rid of our range specs on error */
     if (range_err) {
         debug(33, 2) ("clientBuildRangeHeader: will not do ranges: %s.\n", range_err);
Received on Tue Nov 02 1999 - 08:00:07 MST