How To Increase Apache Requests Per Second

Last updated on August 10th, 2020 at 03:05 am

By default, Apache web server is configured to support 160 requests per second. As your website traffic increases, Apache will start dropping additional requests and this will spoil customer experience. Here’s how to increase Apache requests per second.

Table of Contents

How Many Requests Can Apache Handle Per Second

By default, Apache Request limit is 160 requests per second, that is, Apache can handle up to 160 requests per second, without any modification.

How To Increase Apache Requests Per Second

Here are the steps to increase Apache requests per second.

1. Install MPM module

We need to install MPM Apache module to be able to increase Apache requests per second. You can use mpm_worker or mpm_event module for this, instead of mpm_prefork module which consumes a lot of memory.

You can easily install MPM module in Apache with following command

CentOS7/RHEL7: adjust /etc/httpd/conf.modules.d/00-mpm.conf

Comment the line LoadModule mpm_prefork_module modules/mod_mpm_prefork.so by adding # in front of it

Uncomment the line LoadModule mpm_worker_module modules/mod_mpm_worker.so by removing # in front of it.

Ubuntu/Debian: use a2dismod / a2enmod to disable mpm_prefork and enable mpm_worker

$ a2dismod mpm_prefork
$ a2enmod mpm_worker

Bonus Read : How to Install mod_wsgi in Apache on Ubuntu

2. Increase Max Connections in Apache

Open MPM configuration file:

CentOS/RHEL

$ sudo vi /etc/httpd/conf.modules.d/00-mpm.conf

Ubuntu/Debian

$ sudo vi /etc/apache2/mods-available/mpm_worker.conf

Bonus Read : How to Increase Max Connections in Apache

You will see the following lines

StartServers 5
MinSpareServers 5
MaxSpareServers 10
MaxRequestWorkers 150
MaxConnectionsPerChild 0

You can change them to the following configuration to increase max requests per second. The following configuration supports up to 8000 concurrent users

<IfModule mpm_worker_module>
ServerLimit 250
StartServers 10
MinSpareThreads 75
MaxSpareThreads 250
ThreadLimit 64
ThreadsPerChild 32
MaxRequestWorkers 8000
MaxConnectionsPerChild 10000
</IfModule>

You can also add the above lines to Apache web server configuration file, or Virtual host configuration file.

Let’s quickly look at the parameters

Serverlimit – Maximum number of Apache processes
StartServers – Number of processes to start when you start running Apache
MinSpareThreads/MaxSpareThreads – Number of threads to keep idle without being killed
ThreadsPerChild – Number of threads per process
MaxRequestWorkers – Number of concurrent connections to be supported. This is the main directive that you need to change to increase max connections in Apache
MaxConnectionsPerChild – Number of connections to be handled by each child before it is killed

Bonus Read : How to Increase Max URL Length in Apache