[squid-users] refresh_pattern and same objects

[Eliezer Croitoru]

On 02/09/2015 13:00, Yuri Voinov wrote:
>
> I'm getting a very high hit ratio in my cache.And I do not intend to
> lower its with myself. Enough and that on the opposite side of the
> thousands of webmasters counteract caching their content on its own
> grounds. Beginning from YouTube.

Well, Most sane server side caches do allow and work with a 304 
validation and in many cases it's good.
Notice that I have not seen an access.log analyzer that counts 
re-validation successfully until now.
I do not know what the situation of your bandwidth usage or needs but 
there is a term which called "over caching" and it depends on the 
environment.
If you see that the cache is working for you with higher numbers then 
30% consider that your cache maybe is caching more then the standard cache.
I am pretty sure that a domain analysis can find the more accurate 
refresh_patterns that can leave you with high cache hit ratio and still 
make the cache less vulnerable to config mistakes.

Maybe clients didn't complained until now but it doesn't states that 
they do not have any issues. It's just that they didn't got to you yet.
If you are using 3.4.X and up you are in a better place then in 3.2.X 
and older version so squid should be safe enough for a very ambitious 
config file.

All The Bests,
Eliezer

* Thanks for sharing the refresh_patterns discussion with others