<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<span id="result_box" class="" lang="en"><span class="hps">I</span>
<span class="hps">understand perfectly</span><span>.</span> <span
class="hps">However</span> <span class="hps">-</span> <span
class="hps">I changed</span> <span class="hps">version of</span>
<span class="hps">the proxy</span> <span class="hps">and</span> <span
class="hps">everywhere</span> <span class="hps">at the same
time</span> <span class="hps">changed</span> <span class="hps">the
headlines</span><span>?</span> <span class="hps">Now</span> <span
class="hps">I will return</span> <span class="hps">the version</span>
<span class="hps">3.4 and</span> <span class="hps">everything
will be</span> <span class="hps">as it was.</span> <span
class="hps">I already</span> <span class="hps">did</span><span>.<br>
<br>
</span></span><br>
<div style="" id="gt-input-tool">
<div id="itamenu"><span class="ita-kd-inputtools-div"></span></div>
</div>
<div id="gt-src-c" class="g-unit">
<div id="gt-src-p"> </div>
</div>
<div id="gt-res-content" class="almost_half_cell">
<div dir="ltr" style="zoom:1">
<div id="tts_button"><object
type="application/x-shockwave-flash"
data="//ssl.gstatic.com/translate/sound_player2.swf"
id="tts" height="18" width="18"></object></div>
<span id="result_box" class="" lang="en"><span class="hps">That's
why I</span> <span class="hps">ask the question</span> <span
class="hps">-</span> <span class="hps">what has changed</span>
<span class="hps">so much</span> <span class="hps">that</span>
<span class="hps">the same</span> <span class="hps">configuration</span>
<span class="hps">I get</span> <span class="hps">10 times</span>
<span class="hps">smaller</span> <span class="hps">cache hit</span><span>.</span></span></div>
</div>
<br>
<div class="moz-cite-prefix">26.10.15 16:29, Eliezer Croitoru пишет:<br>
</div>
<blockquote cite="mid:562E0073.4090302@ngtech.co.il" type="cite">Hey
Yuri,
<br>
<br>
What have you tried until now to understand the situation of the
issue?
<br>
From your basic question I was sure that you ran some tests on
some well defined objects.
<br>
To asses the state of squid you would need some static objects and
some changing objects.
<br>
You would also be required to test using a simple UA like a
script\wget\curl and using a fully fledged UA such as
chrome\firefox\explorer\opera\safari.
<br>
<br>
I can try to give you couple cache friendly sites which will show
you what the basic status of squid.
<br>
In the past someone here asked how to cache the site:
<a class="moz-txt-link-freetext" href="http://djmaza.info/">http://djmaza.info/</a>
<br>
which by default is built using lots of static content such as
html pages, pictures and good css and also implements cache
headers nicely.
<br>
I still do not know why wordpress main pages do not have a valid
cache headers, and what I mean by that is: Is it not possible to
have a page cached for 60 seconds? how much updates can accrue in
60 seconds? would a "must-revalidate" cost that much compared to
what there is now?(maybe it does).
<br>
Another one would be <a class="moz-txt-link-freetext" href="https://www.yahoo.com/">https://www.yahoo.com/</a> which is mostly fine
with cache and define their main page with "Cache-Control:
no-store, no-cache, private, max-age=0" since it's a news page
which updates too much.
<br>
<br>
I was looking for cache testing subjects and I am still missing
couple examples\options.
<br>
<br>
Until now what have mainly used for basic test was redbot.org and
a local copy of it for testing purposes.
<br>
And while writing to you looking for test subjects I have seen
that my own web server have a question for squid.
<br>
I have an example case which gives a great example how to "break"
squid cache.
<br>
So I have my website and the main page:
<br>
<a class="moz-txt-link-freetext" href="http://ngtech.co.il/">http://ngtech.co.il/</a>
<br>
<a class="moz-txt-link-freetext" href="https://ngtech.co.il/">https://ngtech.co.il/</a> (self signed certificate)
<br>
<br>
that would be cached properly by squid!
<br>
If for any reason I would remove the Last-Modified header from the
page it would become un-cachable in squid (3.5.10) with default
settings.
<br>
Accidentally I turned ON the apache option to treat html as php
using the apache configuration line:
<br>
AddType application/x-httpd-php .html .htm
<br>
<br>
Which is recommended to be used by the first google result for
"html as php".
<br>
Once you will try the next page(with this setting on):
<br>
<a class="moz-txt-link-freetext" href="http://ngtech.co.il/squidblocker/">http://ngtech.co.il/squidblocker/</a>
<br>
<a class="moz-txt-link-freetext" href="https://ngtech.co.il/squidblocker/">https://ngtech.co.il/squidblocker/</a> (self signed certificate)
<br>
<br>
You will see that it is not being cached at all.
<br>
Redbot.org claims that the cache is allowed it's own freshness for
the object but squid (3.5.10) will not cache it what so ever and
no matter what I do.
<br>
When I am removing "http as php" tweak the page response with a
Last-Modified header and can be cached again.
<br>
<br>
I am unsure who is the culprit for the issue but I will ask about
it in a separated thread *if* I will get no response here.(sorry
for partially top-posting)
<br>
<br>
Eliezer
<br>
<br>
<br>
On 25/10/2015 21:29, Yuri Voinov wrote:
<br>
<blockquote type="cite">In a nutshell - I need no possible
explanation. I want to know - it's a
<br>
bug or so conceived?
<br>
<br>
26.10.15 1:17, Eliezer Croitoru пишет:
<br>
<blockquote type="cite">Hey Yuri,
<br>
<br>
I am not sure if you think that Squid version 4 with extreme
low hit
<br>
</blockquote>
ratio is bad or not but I can understand your sight about
things.
<br>
<blockquote type="cite">Usually I am redirecting to this page:
<br>
</blockquote>
<a class="moz-txt-link-freetext" href="http://wiki.squid-cache.org/Features/StoreID/CollisionRisks#Several_real_world_examples">http://wiki.squid-cache.org/Features/StoreID/CollisionRisks#Several_real_world_examples</a>
<br>
<blockquote type="cite">
<br>
But this time I can proudly say that the squid project is
doing things
<br>
</blockquote>
the right way while it might not be understood by some.
<br>
<blockquote type="cite">Before you or anyone declares that there
is a low hit ratio due to
<br>
</blockquote>
something that is missing I will try to put some sense into how
things
<br>
looks in the real world.
<br>
<blockquote type="cite">Small thing from a nice day of mine:
<br>
I was sitting talking with a friend of mine, a MD to be exact
and
<br>
</blockquote>
while we were talking I was just comforting him about the
wonders of
<br>
Computers.
<br>
<blockquote type="cite">He was complaining on how the software
in the office moves so slow and
<br>
</blockquote>
he needs to wait for the software to response with results. So I
<br>
hesitated a bit but then I asked him "What would have happen if
some MD
<br>
here in the office will receive the wrong content\results on a
patient
<br>
from the software? he described it to me terrified from the
question 'He
<br>
can get the wrong decision!' and then I described to him how he
is in
<br>
such a good place when he doesn't need to fear from such
scenarios.
<br>
<blockquote type="cite">In this same office Squid is being used
for many things and it's
<br>
</blockquote>
crucial that besides the option to cache content the possibility
to
<br>
validate cache properly will be set right.
<br>
<blockquote type="cite">
<br>
I do understand that there is a need for caches and sometimes
it is
<br>
</blockquote>
crucial in order to give the application more CPU cycles or more
RAM but
<br>
sometimes the hunger for cache can consume the actual
requirement for
<br>
the content integrity and it must be re-validated from time to
time.
<br>
<blockquote type="cite">
<br>
I have seen couple times how a cache in a DB or other levels
results
<br>
</blockquote>
with a very bad and unwanted result while I do understand some
of the
<br>
complexity and caution that the programmers take when building
all sort
<br>
of systems with cache in them.
<br>
<blockquote type="cite">
<br>
If you do want to understand more about the subject pick your
favorite
<br>
</blockquote>
scripting language and just try to implement a simple object
caching.
<br>
<blockquote type="cite">You would then see how complex the task
can be and you can maybe then
<br>
</blockquote>
understand why caches are not such a simple thing and specially
why
<br>
ignore-no-cache should not be used in any environment if it is
possible.
<br>
<blockquote type="cite">
<br>
While I do advise you to not use it I would hint you and
others on
<br>
</blockquote>
another approach to the subject.
<br>
<blockquote type="cite">If you are greedy and you have hunger
for cache for specific
<br>
</blockquote>
sites\traffic and you would like to be able to benefit from
over-caching
<br>
there is a solution for that!
<br>
<blockquote type="cite">- You can alter\hack squid code to meet
your needs
<br>
- You can write an ICAP service that will be able to alter the
<br>
</blockquote>
response headers so squid would think it is cachable by default.
<br>
<blockquote type="cite">- You can write an ECAP module that will
be able to alter the response
<br>
</blockquote>
headers ...
<br>
<blockquote type="cite">- Write your own cache service with your
algorithms in it.
<br>
<br>
Take in account that the squid project tries to be as fault
tolerance
<br>
</blockquote>
as possible due to it being a very sensitive piece of software
in very
<br>
big production systems.
<br>
<blockquote type="cite">Squid doesn't try to meet the
requirement of "Maximum Cache" and it is
<br>
</blockquote>
not squid that as a caching proxy makes a reduction of any cache
percentage!
<br>
<blockquote type="cite">The reason that the content is not
cachable is due to all these
<br>
</blockquote>
application that describe their content as not cachable!
<br>
<blockquote type="cite">For a second of sanity from the the
squid project, try to contact
<br>
</blockquote>
google\youtube admins\support\operators\forces\what-ever to
understand
<br>
how would you be able to benefit from a local cache.
<br>
<blockquote type="cite">If and when you do manage to contact
them let them know I was looking
<br>
</blockquote>
for a contact and I never managed to find one of these available
to me
<br>
on the phone or email. You cannot say anything like that on the
squid
<br>
project, the squid project can be contacted using an email and
if
<br>
required you can get a hold of the man behind the software(while
he is a
<br>
human).
<br>
<blockquote type="cite">
<br>
And I will try to write it in a geeky way:
<br>
deny_info 302:<a class="moz-txt-link-freetext" href="https://support.google.com/youtube/">https://support.google.com/youtube/</a>
<br>
</blockquote>
big_system_that_doesnt_want_to_be_cached
<br>
<blockquote type="cite">
<br>
Eliezer
<br>
<br>
* P.S If you do want to write an ICAP service or an ECAP
module to
<br>
</blockquote>
replace the "ignore-no-cache" I can give you some code that will
might
<br>
help you as a starter.
<br>
<blockquote type="cite">
<br>
<br>
On 25/10/2015 17:17, Yuri Voinov wrote:
<br>
<blockquote type="cite">
<br>
</blockquote>
Hi gents,
<br>
<br>
Pay attention to whether someone from the test SQUID 4 as
extremely low
<br>
of cache hits from the new version? Particularly with respect
to sites
<br>
HTTPS directive "no cache"? After replacing the Squid 3.4 to 4
squid
<br>
cache hit collapsed from 85 percent or more on the level of
5-15
<br>
percent. I believe this is due to the exclusion of support
guidelines
<br>
ignore-no-cache, which eliminates the possibility of
aggressive caching
<br>
and reduces the value of caching proxy to almost zero.
<br>
<br>
This HTTP caches normally. However, due to the widespread use
of HTTPS
<br>
trends - caching dramatically decreased to unacceptable
levels.
<br>
<br>
Noticed there anyone else this effect? And what is now with
caching?
<br>
<br>
<blockquote type="cite">
<br>
</blockquote>
</blockquote>
</blockquote>
_______________________________________________
<br>
squid-users mailing list
<br>
<a class="moz-txt-link-abbreviated" href="mailto:squid-users@lists.squid-cache.org">squid-users@lists.squid-cache.org</a>
<br>
<a class="moz-txt-link-freetext" href="http://lists.squid-cache.org/listinfo/squid-users">http://lists.squid-cache.org/listinfo/squid-users</a>
<br>
</blockquote>
<br>
</body>
</html>