I am a self confessed page speed optimisation addict so when I started reading up on Progressive Web Apps (PWA) and using service worker caching and precaching, I got all excited by the possibilities of making my sites and forums load pages even faster :)

On July 22, 2018 I started reading up on PWA and service workers doing simple test static HTML pages. I tried various methods, libraries and frameworks for service workers and settled on using Google Workbox.

Then once I had a basic handle on them, I started converting my centminmod.com site over to PWA. …

As part of this How to boost Centmin Mod LEMP stack performance guide, I did some benchmark comparisons for each of the supported Centmin Mod Nginx compiler build options for GCC 4.8.5, 5.3.1, 6.3.1, 7.2.1, 8.0 and Clang 3.4.2, 4.0.1, 5.0.1, 6.0.0 with the standard default Nginx Zlib library versus Cloudflare’s Zlib performance fork library.

I did load testing benchmarks using my own custom forked version of wrk load testing tool testing gzip compressed requests so as to properly test each Zlib library https://github.com/centminmod/wrk/tree/centminmod.

As you can see, Cloudflare’s Zlib performance fork library has around 22–29% better performance than the default Centmin Mod Nginx Zlib library performance which is compiled against Zlib v1.2.11 on CentOS 7.4.

Relevant Links

• You can view the raw wrk benchmark numbers here.
• Check out the How to boost Centmin Mod LEMP stack performance Guide

Most recent Linux Kernel updates have been to address Meltdown & Spectre vulnerabilities. The first Linux Kernel patch update was to address Meltdown and reportedly it can result in between 5–30% performance overhead while others report it at 5–20%. I decided to do my own tests on CentOS 7.4 64bit OVH dedicated server running Centmin Mod 123.09beta01 branch LEMP stack with Nginx 1.13.8 to see how the updated CentOS 7.4 3.10.0–693.11.6 Linux Kernel impacted Nginx static file serving performance with PTI enaabled vs PTI disabled (no Retpoline Kernel fixes are available in CentOS Linux Kernel as yet).

Full results here.

Posted comparison PHP-FPM benchmarks on Centmin Mod LEMP stack to compare PHP 7.2.0 RC6 vs 7.1 vs 7.0 vs 5.6 versions. PHP 7 versions are tested both with Profile Guided Optimisations (PGO) and without PGO.

A Linode StackScript allows you to customise and automate your Linode VPS server deployments. I’ve created an official public StackScript for my Centmin Mod LEMP stack installation for CentOS 7. You can follow the development on official forums here.

There are optional extras you can choose to customise your Linode VPS server deployments including adding your Pushover.net email so you can get a push notification alert to your mobile devices when the StackScript completes it run.

To use a Linode StackScript you need to rebuild a Linode VPS with a StackScript as outlined here or follow step by step illustrative how to guide here.

Centmin Mod LEMP stack auto installer installs an auto optimised Nginx 1.11.x, MariaDB 10 and PHP-FPM web stack on CentOS. The latest 123.09beta01 adds a new addon called acmetool.sh which integrates Letsencrypt SSL certificate issuance, renewal and re-issues via a 3rd party bash shell client, acme.sh.

The acmetool.sh addon outline is at https://centminmod.com/acmetool and has two modes of operation

• command line
• menu mode

The command line mode to issue Letsencrypt SSL certificate + auto generate an Nginx HTTP/2 based HTTPS vhost site is as simple as running these commands:

For staging test Letsencrypt SSL certificate + Nginx HTTP/2 HTTPS vhost…

Centmin Mod LEMP stack’s newest addon, acmetool.sh is about to begin public beta testing allowing Nginx users to auto generate new Nginx vhost sites with HTTP/2 based HTTPS support out of the box with free Letsencrypt SSL certificates :)

What is addons/acmetool.sh ?

Basically, addons/acmetool.sh is a standalone Centmin Mod Addon added to Centmin Mod 123.09beta01 branch which extends the feature set of Centmin Mod to allow users to automatically create Nginx based vhost site domain accounts and automatically obtain and configure the site to use free domain validated Letsencrypt SSL certificates and serve your site(s) via Nginx HTTP/2 protocol based HTTPS. It is one of the last remaining pieces needed before pushing Centmin Mod 123.09beta01 branch to stable release.