Re: refresh pages

Ubaldo Lescano wrote:

> It exists a client who updates his Web page all the days, but does not
> see reflected east change after long time (almost a day), which I have
> been able to see is that squid gathers this page of memory.

Most likely also worsened a lot by your aggressive caching rules. Your
refresh_pattern ruleset said that any HTML page is to be considered
fresh for 30 days regardless of how often it gets modified.

The distributed default rules will cache pages as fresh for 20% of their
age or at most 3 days. Any cached pages older than this will be
revalidated when visited.

> as I can optimize it so that the time of refresh is smaller to the
> normal one?

Of course. You can set up any refresh patterns you like. For content you
know are being changed frequently you are recommended to set up low
refresh_patterns or in some cases even use the no_cache tag to stop them
from being cached at all.

Some rules you should obey when you make refresh_pattern configurations:

a) Never set min age to anything else than 0 unless you know exactly
what you are doing and why. Setting a min age can cause pages not
intended for caching to be cached unless you are careful with what the
refresh_pattern matches.

b) The LMT factor (percent) should be quite small. Recommended is at
most 20% for HTML content. Higher values may be used on images.

c) The max age controls the upper bound on staleness. Use it to set a
guaranteed freshness level. The default patterns uses 3 days for HTTP
objects to guarantee that user sees modifications after at most 3 days
even on objects rarely modified.

--
Henrik Nordstrom
Spare time Squid hacker