Re: [squid-users] StoreID - Need help with Yandex videos

On 04/29/2014 05:52 PM, Vdoctor wrote:
> Eliezer,
>
> Thanks for the tips. ;o)
> We are doing tests with the StoreID, do you know why many requests are as TCP_MISS ?
> (we use your original ruby file and settings as indicated from the Squid website)
>
> Bye Fred
Hey Fred,

Each and every one of the objects should be tested by itself.
The last time I checked for example the linux repository mirror servers
use ETAG.
One of the issues is that the ETAG is a calculated value based on couple
parameters.
Most of the server admins tend to leave it as default which is inode
number + modification time + size.
I think it is using crc32 calculation which is supported by most of the
CPUs (if not all) these days and should be fast.

One of the issues is that the inode number is not the same on each and
every machine for the exact same file.
So if you have two http requests which squid request with an etag
condition and it's not the same you will see many MISS.
Also note that squid 3.4 has other states then just plain MISS and HIT
but also UNMODIFIED variations etc.
squid 3.4 does a more complex validation of the responses vs response
and requests which can lean to a situation which a miss-configuration or
bad configuration on the squid host or the content provider(http site)
would cause less caching HITs and no option to validate the content.
I have noticed that some sites that uses drupal for example tends to
force cache unfriendly pages.
Also note that some content just cannot be cached by it's structure.

I would say that a "copy paste" for some websites is OK by me but the
sites owners wants money and couple other things to feel their site is
running.

I wanted to cook a basic validation of testing cachiness with
debug_options to validate if the object has the right properties to be
cached.

It is possible to find it out but I yet to have found the right debugs
due to a missing debug level and part in debug_options.
for now it's only pointing to the line in code.

kinkie, amos: Do you think that adding the debug section and level is
the right thing? can it be done? will it heart something?

Eliezer
Received on Tue Apr 29 2014 - 15:13:30 MDT