Tutorials on AnyStack

How to install a Mastodon instance on Ubuntu 16.04 LTS

Thu, 06 Apr 2017 10:06:00 +0000

Have you already the new open-source social network Mastodon ? I have launched few days ago my own instance to contribute to this project.

If you want to launch your own instance, here a quick tutorial to install mastodon on a Ubuntu 16.04 LTS server with Nginx as a reverse-proxy and Cloudflare CDN/SSL.

To follow the steps of this tutorial, a user with sudo rights is enough, you don’t need to login as root.

Install the dependencies

sudo apt-get update

Install nodejs

curl -sL https://deb.nodesource.com/setup_6.x | sudo bash -
sudo apt-get install imagemagick ffmpeg libpq-dev libxml2-dev libxslt1-dev nodejs
sudo npm install -g yarn

Install redis-server

sudo apt-get install redis-server redis-tools

Install Postgresql

sudo apt-get install postgresql postgresql-contrib

sudo su - postgres
psql
CREATE USER mastodon CREATEDB;
\q

You will also have to enable ident authentication so users can login without password

sudo sed -i '/^local.*postgres.*peer$/a host all all 127.0.0.1/32 ident' \
/etc/postgresql/9.?/main/pg_hba.conf

And to install the ident daemon :

sudo apt-get install pidentd
sudo systemctl enable pidentd
sudo systemctl start pidentd
sudo systemctl restart postgresql

Install Ruby

Install the dependencies

sudo apt-get install autoconf bison build-essential libssl-dev libyaml-dev libreadline6-dev zlib1g-dev libncurses5-dev libffi-dev libgdbm3 libgdbm-dev

Create a user mastodon without password :

adduser --disabled-password --disabled-login mastodon

Then login as mastodon :

su - mastodon

Install rbenv and rbenv-build

git clone https://github.com/rbenv/rbenv.git ~/.rbenv
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
source ~/.bashrc

We have to logout to apply the bash modification, and we install ruby-build.

exit
su - mastodon
git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build

Then install ruby 2.4.1 for mastodon :

rbenv install 2.4.1
rbenv global 2.4.1

You can check the ruby version installed with the command :

ruby -v

Mastodon installation

We have installed all the dependencies required to setup Mastodon, so we can now clone the github repository. We use git checkout to select the last release instead of the master branch.

cd ~
git clone https://github.com/tootsuite/mastodon.git live
cd live
git checkout $(git tag | tail -n 1)

Install bundler to manage the dependencies and disable the gem documentation

echo "gem: --no-document" > ~/.gemrc
gem install bundler --no-ri

Then launch the installation

bundle install --deployment --without development test
yarn install

You can now copy the configuration sample file and edit with your own informations

cp .env.production.sample .env.production
nano .env.production

You have to add the following informations :

# Service dependencies
REDIS_HOST=localhost
REDIS_PORT=6379
DB_HOST=/var/run/postgresql
DB_USER=mastodon
DB_NAME=mastodon_production
DB_PASS=
DB_PORT=5432

# Federation
LOCAL_DOMAIN=yourdomain.com
LOCAL_HTTPS=true

Ainsi que la partie SMTP qui permettra aux utilisateurs de confirmer leur inscription :

# E-mail configuration
SMTP_SERVER=mail.yourdomain.com
SMTP_PORT=587
SMTP_LOGIN=noreply@yourdomain.com
SMTP_PASSWORD=YourPassword
SMTP_FROM_ADDRESS=noreply@yourdomain.com

For the application secret part, you can use the command bundle exec rake secret to generate the 3 secret keys, then you have just to copy them into the configuration file.

To setup the database and the assets :

RAILS_ENV=production bundle exec rails db:setup
RAILS_ENV=production bundle exec rails assets:precompile

Adding systemd services

Web service

nano /etc/systemd/system/mastodon-web.service

[Unit]
 Description=mastodon-web
 After=network.target

[Service]
 Type=simple
 User=mastodon
 WorkingDirectory=/home/mastodon/live
 Environment="RAILS_ENV=production"
 Environment="PORT=3000"
 ExecStart=/home/mastodon/.rbenv/shims/bundle exec puma -C config/puma.rb
 TimeoutSec=15
 Restart=always

[Install]
 WantedBy=multi-user.target

Background service

nano /etc/systemd/system/mastodon-sidekiq.service

[Unit]
 Description=mastodon-sidekiq
 After=network.target

[Service]
 Type=simple
 User=mastodon
 WorkingDirectory=/home/mastodon/live
 Environment="RAILS_ENV=production"
 Environment="DB_POOL=5"
 ExecStart=/home/mastodon/.rbenv/shims/bundle exec sidekiq -c 5 -q default -q mailers -q pull -q push
 TimeoutSec=15
 Restart=always

[Install]
 WantedBy=multi-user.target

API service

nano /etc/systemd/system/mastodon-streaming.service

[Unit]
 Description=mastodon-streaming
 After=network.target

[Service]
 Type=simple
 User=mastodon
 WorkingDirectory=/home/mastodon/live
 Environment="NODE_ENV=production"
 Environment="PORT=4000"
 ExecStart=/usr/bin/npm run start
 TimeoutSec=15
 Restart=always

[Install]
 WantedBy=multi-user.target

Then we can enable our systemd services :

systemctl enable /etc/systemd/system/mastodon-*.service

And we can start our mastodon instance :

sudo systemctl start mastodon-web.service mastodon-sidekiq.service mastodon-streaming.service

Add the required crons for mastodon :

crontab -u mastodon -e

RAILS_ENV=production
@daily cd /home/mastodon/live && RAILS_ENV=production /home/mastodon/.rbenv/shims/bundle exec rails mastodon:media:remove_remote

Nginx reverse-proxy setup :

So we have setup mastodon, but to access to our instance directly under https and with our domain, we need to setup a reverse-proxy using Nginx.

At first, install Nginx :

wget -O - https://nginx.org/keys/nginx_signing.key | sudo apt-key add -
sudo echo "deb http://nginx.org/packages/ubuntu/ $(lsb_release -sc) nginx" > /etc/apt/sources.list.d/nginx.list
sudo apt update
sudo apt install nginx

We have now to create our nginx configuration file for ou domain, we will use the configuration based on the Angristan’s model :

nano /etc/nginx/sites-enabled/yourdomain.com

map $http_upgrade $connection_upgrade {
 default upgrade;
 '' close;
}
server {
 listen 80;
 listen [::]:80;
 server_name www.yourdomain.com yourdomain.com;
 return 301 https://votredomaine.com$request_uri;

 access_log /dev/null;
 error_log /dev/null;
}

server {
 listen 443 ssl http2;
 listen [::]:443 ssl http2;
 server_name www.yourdomain.com yourdomain.com;

 access_log /var/log/nginx/yourdomain.com-access.log;
 error_log /var/log/nginx/yourdomain.com-error.log;

 ssl_certificate /etc/letsencrypt/live/fullchain.pem;
 ssl_certificate_key /etc/letsencrypt/live/privkey.pem;
 ssl_protocols TLSv1.2;
 ssl_ciphers EECDH+AESGCM:EECDH+AES;
 ssl_prefer_server_ciphers on;
 add_header Strict-Transport-Security "max-age=15552000; preload";

 keepalive_timeout 70;
 sendfile on;
 client_max_body_size 0;
 gzip off;

 root /home/mastodon/live/public;

 location / {
 try_files $uri @proxy;
 }

 location @proxy {
 proxy_set_header Host $host;
 proxy_set_header X-Real-IP $remote_addr;
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
 proxy_set_header X-Forwarded-Proto https;
 proxy_pass_header Server;
 proxy_pass http://127.0.0.1:3000;
 proxy_buffering off;
 proxy_redirect off;
 proxy_http_version 1.1;
 proxy_set_header Upgrade $http_upgrade;
 proxy_set_header Connection $connection_upgrade;
 tcp_nodelay on;
 }

 location /api/v1/streaming {
 proxy_set_header Host $host;
 proxy_set_header X-Real-IP $remote_addr;
 proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
 proxy_set_header X-Forwarded-Proto https;
 proxy_pass http://127.0.0.1:4000;
 proxy_buffering off;
 proxy_redirect off;
 proxy_http_version 1.1;
 proxy_set_header Upgrade $http_upgrade;
 proxy_set_header Connection $connection_upgrade;
 tcp_nodelay on;
 }

 error_page 500 501 502 503 504 /500.html;
}

You can start nginx with the command :

service nginx start

Then we will use Let’s Encrypt to generate a SSL certificate.

cd /opt
git clone https://github.com/letsencrypt/letsencrypt
cd letsencrypt
./letsencrypt-auto certonly --webroot -w /home/mastodon/live -d www.yourdomain.com -d yourdomain.com --email vous@yourdomain.com --text --rsa-key-size 4096

Updating Mastodon

Mastodon is updated very often, so if you want to keep your instance up-to-date you will have to follow the following steps :

su - mastodon
cd live
gem install bundler --no-ri
git fetch
git checkout v1.X.X
bundle install --deployment --without development test
NODE_ENV=production npm upgrade --global yarn
yarn install
RAILS_ENV=production bundle exec rails assets:clean
RAILS_ENV=production bundle exec rails assets:precompile
RAILS_ENV=production bundle exec rails db:migrate
exit

Then you just have to restart the instance :

sudo systemctl restart mastodon-web.service mastodon-sidekiq.service mastodon-streaming.service

If you need to update ruby with a new release use :

rbenv install 2.4.1
gem install bundler --no-ri

Create your administrator account

You instance is now running properly but you have to register to create your account and then you will be able to set this account as administrator with the following command :

RAILS_ENV=production bundle exec rails mastodon:make_admin USERNAME=votre-utilisateur

My instance mastodon.top

![mastodon.top/images/2017/08/Screenshot_44.png) With VirtuBox, I have launched a Mastodon instance and if you are not registered on Mastodon yet, you can register at mastodon.top. We are already more than 200 users on my instance and enough resources for more users. You can find more informations about the instance on the page about and the real-time monitoring of the server at instance.mastodon.top.

Don’t hesitate to give your opinion on Mastodon, to tell me if there are errors in the tutorial or to ask for help if you want to deploy your own instance.

You can also follow me on Mastodon : thomas_virtubox@mastodon.top

How to upgrade Ghost

Thu, 16 Feb 2017 14:21:00 +0000

If you are using a self-hosted Ghost, you may have sometimes to upgrade it to the new release. To do that, you have at first to download the latest Ghost release. For that create a new folder next your current Ghost folder and download Ghost :

mkdir newghostfolder && cd newghostfolder
wget https://ghost.org/zip/ghost-latest.zip
unzip ghost-latest.zip

You can make a copy of your current ghost folder and you will have to remove the index.js, all the .md and .json and the core folder. But do not delete the config.js file. Then you will have to stop the current Ghost instance by using :

forever stop index.js

Copy the new files over your current folder, and install the new dependencies with :

npm install --production

After than you can restart your instance

NODE_ENV=production forever start index.js

How to setup Magento 2.1.7 with EasyEngine - Nginx & Redis-cache

Mon, 07 Nov 2016 20:49:00 +0000

If you have already setup redis-server for object-caching with WordPress, you are maybe looking for something more powerful to setup ? Magento 2 will be the perfect benchmark for your server. It’s an open source e-commerce software and content management system for e-commerce websites based on the PHP Zend Framework. Magento is compatible with the most advanced caching systems including Varnish, Memcached or Redis.

So in this tutorial, we will see how to setup Magento 2.1.7 with Nginx, php7, Mariadb and Redis-server using EasyEngine.

At first, you need a VPS with ubuntu/debian and at least 2GB RAM. In production, 4GB will be the minimum, when 8GB will be better.

Server setup & configuration

## install easyengine
wget -qO ee rt.cx/ee && bash ee

## install Nginx - php5.6 + php7 - Mariadb - phpmyadmin - redis - memcached
ee stack install --web --admin --php7 --redis

## create your domain vhost (--letsencrypt optional)
ee site create yourdomain.com --mysql --php7

## install php-intl for magento and unzip
apt-get update && apt-get install php7.0-intl unzip

Change the php configuration according to magento documentation :

## change php.ini settings for magento
nano /etc/php/7.0/fpm/php.ini

max_execution_time = 1800
max_input_time = 1800
memory_limit = 4096M
post_max_size = 512M

## add the following lines after the extension declaration : [opcache]
opcache.enable=1
opcache.enable_cli=0
opcache.memory_consumption=128
opcache.interned_strings_buffer=4
opcache.max_accelerated_files=20000
opcache.max_wasted_percentage=5
opcache.validate_timestamps=1
opcache.revalidate_freq=2
opcache.optimization_level=0xffffffff

## restart php7.0-fpm
service php7.0-fpm restart

Magento installation

We have already done almost all the server configuration. Now we have to download magento and to launch the installer.

Download it from the Magento website : https://magento.com/tech-resources/download

To upload it via sftp, set a password for the user www-data with the command

passwd www-data

Then allow shell access for www-data with the command :

usermod -s /bin/bash www-data

After that you will be able to use the sftp client of your choice and to upload the magento archive in your website folder with the correct permissions. If you are looking for a sftp client for Windows, I recommend you Cyberduck.

Then go into your website folder and unzip the magento archive.

cd /var/www/yourdomain.com/htdocs
unzip Magento-CE-2.1.6_sample_data-2017-03-29-04-34-51.zip

## set www-data as the owner of the directory and all magento files
cd .. 
chown -R www-data:www-data htdocs

But to be able to launch the installer with nginx, we have to edit the site configuration, for that we will use the nginx.conf.sample file included with magento.

I have edit this file with the correct settings for EasyEngine and you can download it here : magento.conf

You have just to upload this file in /var/www/yourdomain.com/conf/nginx, because with easyengine, all configurations files in this folder are automatically include in your website configuration.

Then edit your website configuration in /etc/nginx/sites-available/yourdomain.com to look like :

server {

 server_name yourdomain.com www.yourdomain.com;
 set $MAGE_ROOT /var/www/yourdomain.com/htdocs;

 access_log /var/log/nginx/yourdomain.com.access.log rt_cache;
 error_log /var/log/nginx/yourdomain.com.error.log;

 include /var/www/yourdomain.com/conf/nginx/*.conf;
}

Check your nginx configuration with the command nginx -t and apply it with service nginx reload

We can now launch the installation by reaching the domain with our browser

Just follow the step, and use the databases user credentials available in the file /var/www/yourdomain.com/ee-config.php

To run properly, Magento require to add some cronjobs. If you are already logged as www-data, you have just to use the command : crontab -e and to add the following lines. Just replace yourdomain.com with your real domain.

* * * * * php /var/www/yourdomain.com/htdocs/bin/magento cron:run | grep -v "Ran jobs by schedule" >> /var/www/yourdomain.com/htdocs/var/log/magento.cron.log
* * * * * php /var/www/yourdomain.com/htdocs/update/cron.php >> /var/www/yourdomain.com/htdocs/var/log/update.cron.log
* * * * * php /var/www/yourdomain.com/htdocs/bin/magento setup:cron:run >> /var/www/yourdomain.com/htdocs/var/log/setup.cron.log

Some other useful command to get started with the magento cli

## deploy the magento sample data
php bin/magento sampledata:deploy

## upgrade your magento install
php bin/magento setup:upgrade

## Generates DI configuration after setup:upgrade
php bin/magento setup:di:compile

## clean magento cache
php bin/magento cache:clean

## backup magento
php bin/magento setup:backup

Your Magento instance is now running properly, but we want to make it faster. For that we will use redis for session storage and full-page caching. I let you read the Magento DevDocs to understand why Redis is better.

Use redis for session and page cache

So, to use Redis-server, there are no plugins like for WordPress, but we have just to edit the file app/etc/env.php and to set the correct settings to use redis for the session storage and the full page caching instead of files. You can use the following example : env.php

There are two blocks to add to use redis-server, it require to use a database for each block :

session caching

'session' => 
 array (
 'save' => 'redis',
 'redis' => 
 array (
	'host' => '127.0.0.1',
	'port' => '6379',
	'password' => '',
	'timeout' => '2.5',
	'persistent_identifier' => 'magento2:',
	'database' => '1',
	'compression_threshold' => '2048',
	'compression_library' => 'gzip',
	'log_level' => '1',
	'max_concurrency' => '6',
	'break_after_frontend' => '5',
	'break_after_adminhtml' => '30',
	'first_lifetime' => '600',
	'bot_first_lifetime' => '60',
	'bot_lifetime' => '7200',
	'disable_locking' => '0',
	'min_lifetime' => '60',
	'max_lifetime' => '2592000',
 ),

Full-page caching

'cache' =>
array(
 'frontend' =>
 array(
 'default' =>
 array(
 'backend' => 'Cm_Cache_Backend_Redis',
 'backend_options' =>
 array(
 'server' => '127.0.0.1',
 'port' => '6379',
 ),
 ),
 'page_cache' =>
 array(
 'backend' => 'Cm_Cache_Backend_Redis',
 'backend_options' =>
 array(
 'server' => '127.0.0.1',
 'port' => '6379',
 'database' => '3',
 'compress_data' => '0',
 ),
 ),
 ),
),

You can now refresh the Magento cache to make sure you are using Redis. You can also use EasyEngine to install phpRedisAdmin to see the redis databases with ee stack install --phpredisadmin

Multiple stores configuration

That’s one of the main feature of Magento, the ability to host several stores/websites on the same magento instance. At first you have to create a new website, store and store view in the Admin panel. For this part just follow the Magento Guide. Then create your additional nginx vhost with :

ee site create your2domain.com

And edit it to look like :

server {

 server_name your2domain.com www.your2domain.com;
 access_log /var/log/nginx/your2domain.com.access.log ;
 error_log /var/log/nginx/your2domain.com.error.log;

 set $MAGE_ROOT /var/www/yourdomain.com/htdocs;

 index index.html index.htm;

 include /var/www/yourdomain.com/conf/nginx/*.conf;
}

You have to make sure you have included the same magento.conf file than for the main website. After that we have to use the Nginx map directive to pass the values of the Magento variables to nginx, so we will create a file map.conf in /etc/nginx/conf.d with the following content :

map $http_host $MAGE_RUN_CODE {
 yourdomain.com yourdomain-code;
 your2domain.com your2domain-code;
}

So if you want to add another store later, you will just have to create another vhost and to add a line in this file with the new domain and the associated website code. Then edit the file /etc/nginx/fastcgi_params and add the following line at the end :

fastcgi_param MAGE_RUN_TYPE website;
fastcgi_param MAGE_RUN_CODE $MAGE_RUN_CODE;

Reload nginx with nginx -t && service nginx reload and you can now check if your two stores are working properly.

If you have any issue to setup Magento with EasyEngine, post a reply on the Magento thread already available. I will answer to your questions.

Making WordPress faster by running wp-cron with Linux

Thu, 15 Sep 2016 05:54:00 +0000

WordPress use wp-cron to check updates for themes, plugins and some other process but it could have an impact on your website speed because WordPress execute it on every page-loading. So if you have a lot of traffic, it will (no benchmark proof at the moment) delay page loading for users.

So if you are using a linux server (VPS or dedicated), you can easily create a cron job to run it each 5 minutes or each 10 minutes. But remember WordPress need wp-cron to work properly, so don’t disable it totally !

To disable wp-cron, just add the following line in wp-config.php :

define('DISABLE_WP_CRON', true);

Then to add a cronjob you have to a :

## Run the crontab with your server or vhost user 
crontab -u yourserveruser -e

## method 1 : using curl to run the script
*/10 * * * * curl http://example.com/wp-cron.php > /dev/null 2>&1

## method 2 : using php to run it
*/10 * * * * cd /var/www/example.com/htdocs; php /var/www/example.com/htdocs/wp-cron.php > /dev/null 2>&1

The first method use PHP-CGI when the second use PHP-CLI, the only difference is CLI does not have time limit to run a script. Because this way, the wp-cron will not impact page loading speed, it’s highly recommended to use linux cron instead of default WordPress cron.

You can change */10 with */5 to run the cron each 5 minutes instead of each 10 minutes.

How to use Nginx as reverse proxy with Docker

Sun, 04 Sep 2016 06:57:00 +0000

I have already write some articles about EasyEngine, and I’m really in love with this command line tool, because it make Nginx easier to use than Apache. But I haven’t talk about all functionality of EE yet. If it provide you the ability to setup a WordPress website easily, you can also use EasyEngine to create a vhost for a static html website … Or use Nginx as a reverse proxy !

And that make of EE the most complete tool available to use Nginx without having to read thousands of documentation pages to understand how to create a vhost. But don’t worry, this article will not only talk about this awesome tool which is EasyEngine.

I have used docker several times in the past, because it’s the fastest way to test an application without having to setup a VPS especially for that. But to run several Docker containers in a single VPS, it could quickly be a problem because some container provide you the ability to use a domain like WordPress for example. And some other will use directly your VPS IP and the port of your choice, which is not very friendly when your app is running on http://192.168.0.1:3000 …

That’s why we will use Nginx to act as a reverse proxy for our Docker containers, and we will be able to run several containers on the same server and to access them with the domain of our choice. So the first step is to install Docker. Don’t worry you should not need to read the documentation if you are using a VPS with a recent linux distribution and a kernel 3.13+

### install Docker with a single command on debian/ubuntu/centos
wget -qO- https://get.docker.com/ | sh

Docker is now running on your server ! So let’s install EasyEngine :

## Install EasyEngine Debian7/8 or Ubuntu 14.04/16.04 LTS
wget -qO ee rt.cx/ee && bash ee

So we have now Docker and EasyEngine installed and we can launch our first Docker App before routing it with Nginx. We will start with Rocket.Chat, a complete live chat solution to build a community or to provide live support.

## Launch MongoDB container 
docker run --name db -d mongo:3.0 --smallfiles

## Run Rocket.Chat linked to the db and expose port 3000
docker run --name rocketchat -p 3000:3000 --env ROOT_URL=http://localhost --link db -d rocket.chat

So you should be able to access to Rocket.Chat using http://YOUR-VPS-IP:3000. And to use Nginx as reverse proxy with your domain :

ee site create yourdomain.com --proxy=127.0.0.1:3000

That’s it ! You can now use http://yourdomain.com to access to Rocket.Chat

Some other apps to run with Nginx as reverse proxy :

## Hastebin
docker run --name redis -d redis
docker run --name hastebin -d -p 7777:7777 --link redis:redis -e STORAGE_HOST=redis rlister/hastebin

## Pasteboard
docker run --name pasteboard -e ORIGIN=mydomain.tld -e MAX=7 -v /srv/pasteboard/images:/pasteboard/public/storage -p 4000:4000 anthodingo/docker-pasteboard

Remove Query strings and add featured images in WordPress feeds

Thu, 30 Jun 2016 00:45:00 +0000

A small post today to share with you a small tips to remove all the queries strings from WordPress static assets, and also to add featured images of your posts in the WordPress feeds.

Go into your WordPress dashboard > Appearance > Editor
Then find the file functions.php of your theme
Add this code at the end of functions.php

//remove queries from static assets
function _remove_script_version( $src ){
$parts = explode( '?ver', $src );
return $parts[0];
}
add_filter( 'script_loader_src', '_remove_script_version', 15, 1 );
add_filter( 'style_loader_src', '_remove_script_version', 15, 1 );

// Include thumbnails is the RSS feed
function rss_post_thumbnail($content) {
global $post;
if(has_post_thumbnail($post->ID)) {
$content = '<p>' . get_the_post_thumbnail($post->ID) .
'</p>' . get_the_content();
}
return $content;
}
add_filter('the_excerpt_rss', 'rss_post_thumbnail');
add_filter('the_content_feed', 'rss_post_thumbnail');

You can now try with GTMetrix.com if you have succefully remove the query strings. For the feed, you can test it with any RSS feed reader. Your WordPress feed are normally available at http://yourdomain.com/feed/.

Linux & SSD : How to speed up your VPS

Tue, 28 Jun 2016 00:41:00 +0000

When you want to buy a VPS, most of them use SSD, because a SSD have a better capacity for reading/writing than a Hard Drive and it also have a response time up to 40x faster than HDD.

But there are some small configuration to edit to get the best performances with your SSD as linux systems are not totally optimized for them.

So we will see how to speed up your VPS and how to configure debian/ubuntu to use a SSD properly. For a new install of a server the rules are :

Use a recent linux system : Kernel 3.60+
Keep some free space on a disk (5-15%)
Use ext4
in /etc/fstab add the noatime setting

# / was on /dev/sda1 during installation
UUID=33XXX-XXXX / ext4 noatime,errors=remount-ro 0 1

Limit the swap usage :

If you use :

cat /proc/sys/vm/swappiness

The system should answer 60. So you just have to add the line below in /etc/sysctl.conf

vm.swappiness=1

Then reboot your system. And it's done your VPS should already be faster