I installed varnish as well on my server , but the performance did not change , The http://www.webpagetest.org/ says caching system does not enable on your server , i'm using default configuration of varnish , it's my header :
status: HTTP/1.1 200 OK
Server: Apache
X-Powered-By: PHP/5.3.29
P3P: CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM"
Expires: Mon, 1 Jan 2001 00:00:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
Set-Cookie: 73ab794b527721e09d2124da5815cf79=2f8ca1fed15724e75f5bf3824a26a9cd; path=/; HttpOnly
Last-Modified: Thu, 25 Sep 2014 08:28:53 GMT
Content-Type: text/html; charset=utf-8
Content-Length: 77965
Accept-Ranges: bytes
Date: Thu, 25 Sep 2014 08:28:53 GMT
X-Varnish: 1531877383
Age: 0
Via: 1.1 varnish
Connection: close
Best Answer
I will see if i can help for any future views of this issue, There are a number of things that will cause Varnish not to cache content. You will need to work through all of them and hopefully have a good logging / metrics setup so you can identify which pages / resources are not responding from cache.
Your cache control headers were:
To have this particular request cachable you need to fix:
Expires: Mon, 1 Jan 2001 00:00:00 GMTThis tells Varnish not to cache
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0This tells Varnish not to cache (Varnish 4+, Varnish 3 will still cache this)
Set-Cookie: 73ab794b527721e09d2124da5815cf79=2f8ca1fed15724e75f5bf3824a26a9cd; path=/; HttpOnlyVarnish will not cache any response with Set-Cookie
In order to tackle metrics / logging so that you can get visibility of all requests i have written about Varnish setup options: https://www.section.io/varnish-install-quick-and-detailed/