Any kind of virtualization decreases server performance, so we will use a bare metal server (with 8 threads and 32 GB RAM in this example) with SSD storage. In order to benefit from the latest kernel features and software packages, the server will run Ubuntu 18.04. For the actual software stack, we have chosen the fastest options available: Nginx, PHP 7.3, PHP-FPM, Percona 8.0 and Redis.

Installing the required packages

Run the following commands to install in order Percona Server 8, PHP 7.3 and related modules, Nginx and Redis. While installing Percona, select the legacy authentication mode and remember the admin password, since you will need it later.

wget https://repo.percona.com/apt/percona-release_latest.$(lsb_release -sc)_all.deb dpkg -i percona-release_latest.$(lsb_release -sc)_all.deb percona-release setup ps80 apt install percona-server-server apt install software-properties-common add-apt-repository ppa:ondrej/php apt update apt install php7.3 apt purge apache2 apt install nginx apt install zip unzip apt install php7.3-fpm php7.3-cli php7.3-curl php7.3-gd php7.3-intl php7.3-mysql php7.3-mbstring php7.3-zip php7.3-xml apt install redis

Configure Redis

We will start by configuring Redis to only use RAM for caching and never write to the disk, since memory is much faster and provides a performance boost. Edit the /etc/redis/redis.conf file with your favorite text editor and start by commenting the lines that instruct Redis to save DB snapshots on disk:

save 900 1 save 300 10 save 60 10000

You will then have to add two lines at the end of the file, the first one configures the maximum memory (this depends on the RAM available on your server), while the second forces the deletion of old keys:

maxmemory 2G maxmemory-policy allkeys-lru

Save your changes and restart the service:

systemctl restart redis-server

Configure Nginx

We will not detail all the configuration options of Nginx, but you will find many excellent config files tuned for Wordpress on the Internet. Modify these files by using your domain name and change the value of fastcgi_pass to the socket used by php 7.3. You will also have to create a folder structure for the fastcgi_cache used by Nginx, as well as setup the proper permissions:

mkdir /var/www/cache mkdir /var/www/cache/wordpress chown www-data:www-data /var/www/cache/ -R

Since you don’t have a SSL certificate yet, comment out the relevant lines in the second server block for now. Remove the default config file in /etc/nginx/sites-enabled/ and create a symlink from your file in /etc/nginx/sites-available/ to this folder in order to activate it. You can now restart the Nginx service:

systemctl restart nginx

Create a user and database for Wordpress

Wordpress needs a local database, so you’ll have to configure one before installing it.

Connect to Percona from the command line:

mysql -u root -p

Execute these commands in order, to setup the database, user and privileges:

CREATE DATABASE database_name; CREATE USER 'user_name'@'localhost' IDENTIFIED WITH mysql_native_password BY 'strong_password'; GRANT ALL PRIVILEGES ON database_name.* TO'user_name'@'localhost'; FLUSH PRIVILEGES; Exit

Install Wordpress

It is time to download and install the latest version of Wordpress, with the following commands:

wget https://wordpress.org/latest.zip unzip latest.zip -d /var/www/ chown www-data:www-data /var/www/wordpress -R rm latest.zip

You can now access the domain in a browser and complete the installation, enter the database credentials configured in the previous step. Go through all the steps and remember the admin user and password. Wordpress is now installed and working, but some further tweaks are needed.

Get a free SSL certificate

Generating and installing a SSL certificate for your site used to be a complex task but the certbot Nginx plugin makes it trivial. You only have to run three commands, the domain should be the one defined in Nginx’s server name directive, multiple subdomains can be added to the certificate:

add-apt-repository ppa:certbot/certbot apt install python-certbot-nginx certbot --nginx -d your_domain

You will be given the option to redirect all http traffic to https. Certbot will also setup a cronjob that automatically renews the certificate when it expires.

Install a plugin for Redis

Redis is already configured to perform object caching in RAM, but Wordpress can’t use this feature without the correct plugin. The plugin named Redis Object Cache is a better choice than the official WP plugin, so install it from the Dashboard and activate it. You can now navigate to Settings -> Redis and click on Enable Object Cache, if the settings are correct the status should change to Connected.

Optimize PHP and Percona settings

The default PHP and database settings are not optimized for modern websites and have to be changed. Let’s start by editing the PHP configuration file /etc/php/7.3/fpm/php.ini. Look for the following lines and apply these values:

max_execution_time = 5000 memory_limit = 512M upload_max_filesize = 128M post_max_size = 128M



Save the file, then restart php-fpm:

systemctl restart php7.3-fpm

Finally, edit Percona’s configuration file vim /etc/mysql/mysql.conf.d/mysqld.cnf and add these lines under the [mysqld] block:

innodb_buffer_pool_size = 8G innodb_log_file_size = 200M innodb_buffer_pool_instances = 16 innodb_io_capacity = 5000 max_binlog_size = 200M expire_logs_days = 3

After saving the changes, restart Percona:

systemctl restart mysql

That was it, you now have the fastest Wordpress stack possible with the packages currently available! We have tried to make this tutorial as simple to follow as possible, but please contact us by email if you have any questions or would like to suggest additional performance tweaks.

About the Author

Dragos Baldescu is a Level 2 Technical Support Engineer at Bigstep, passionate about Linux and testing out new technologies and solutions.