Yesterday a colleague (Dimitri) tested a tool on this blog. He informed me that Varnish was disabled and PageSpeed may be the cause as this is the last modification I’ve made on the server.
After verification he was totally right ! By default, PageSpeed disable cache by serving HTML files with:
Cache-Control: no-cache, max-age=0 After reading the PageSpeed documentation on that topic, it is clear: PageSpeed needs to know how to purge the cache as it rewrites a lot of elements and it has the control instead of the application.
Following a previous post, I’ve enabled PageSpeed on both wiki and blog deimos.fr.
What I can say is, it’s very important to take the time to test every optimizations you want to add. I experienced for example issues on silly things like :
# Optimize browser rendering pagespeed EnableFilters lazyload_images; Some images weren’t shown if you didn’t refresh once again your page browser. I only had this problem on the blog and not the wiki.
I’ve first heard of Page Speed last year for Apache. I was really waiting a stable version for Nginx and it’s now done. A few days ago, Nicolargo made a post regarding it and that’s what motivated me to go ahead on Page Speed.
PageSpeed speeds up your site and reduces page load time. This open-source webserver module automatically applies web performance best practices to pages and associated assets (CSS, JavaScript, images) without requiring that you modify your existing content or workflow.
I discovered Dotdeb a few months ago and decided to make a quick documentation to install the repository. But before, here is the official explaination of what is the repository made for :
Dotdeb is a repository containing packages to turn your Debian boxes into powerful, stable and up-to-date LAMP servers :
Nginx PHP 5.4 and 5.3, useful PHP extensions : APC, imagick, Pinba, xcache, Xdebug, XHprof… MySQL 5.
I already talked about nftables and it has now been implemented in the 3.13 kernel !
For those who never heard of that, it’s a kernel built in replacement of iptables. All features are not there yet but should be implemented in 3.15.
If you like Packet Filter, you’ll be happy. If you’re not sure of the advantages of it, simply read that short comparison and you’ll be convinced : https://home.
I’ve recently updated some of my tutorials :
Optimizing Hard Drive performances : I’ve updated SSD subject Luks : added more information on how auto mount automatically at boot a crypted partition. Xtrabackup : corrected a non working command LXC : modified containers files to avoid boot issues APT-Pinning : Added the command to install a package from a designed repository Sed : forgotten to add -i option which is so important Vagrant : Added an example to the quick tutorial
Varnish is a real powerful cache solution for web servers. He is unfortunately not able to do it over SSL. Anyway, there is a solution by offloading it with Nginx. Here is a schema to get a better understanding :
Nginx decrypt SSL, pass it in clear to Varnish. If Varnish got it, replies to Nginx which crypt back data to send to user.
I’ve made a full documentation to get it working well, follow the link.
