Re: Expires: headers for Packages.gz, Sources.gz
On Sat, 10 Feb 2001, Matt Zimmerman wrote:
> > Which is the header APT sends, with a 1 day old setting by default. If you
> > set that to 0 say (there is a configuration setting), then squid is required
> > to never return a non-validated response.
> max-age. However, max-age=1 day will not have the same effect as the Expires:
> header I proposed. Unless I am mistaken, max-age refers to the maximum time
> since the object was last refreshed (newly retrieved or IMS/Not Modified).
If you use Expires in the absolute mode then you are correct, however that
is not a good idea because of timezone skew on the mirrors, and the fact
that we don't actually update our package files every day unless they have
Using max-age is a reasonable compromise, some people might want to drop
the timer to an hour or a half day or something, but primarily it is
intended so that if you run apt-get at the same time evey day you will get
new package files.
Really though, the way APT does IMS queries they are *cheap*, even setting
a 0 max-age for your cache should not cause noticable performace problems.