WordPress is one of the most demanding content management system of recent days. Most of the users these days use wordpress for their blogs or websites. Around 85% sites of our servers are using wordpress and most of the clients are utilizing multiple wordpress blogs for their business. WordPress has been found to be using pretty good sum of CPU and Memory. Today’s shared hosting environments are more limited based on the CPU and memory rather than the Space and Bandwidth. It is always a wiser choice to spend little amount of time to reduce the overall cpu usage. This makes the blog running faster and hosting companies feel good to host sites which are nicer to their CPUs :) Here are some tips to reduce the CPU usage on a wordpress blog and improve the site performance.

One of the first plugin I suggest all the wordpress users to install is “wp-super-cache”. You can download this plugin here:

http://wordpress.org/extend/plugins/wp-super-cache/

It is pretty easy to install. But a documentation can always be found in wordpress site:

http://wordpress.org/extend/plugins/wp-super-cache/installation/

wp-super-cache is the fastest caching plugin for wordpress blogs. It is always better to serve it from cache instead of running select command for each user of your blog. Enabling super cache would potentially reduce the cpu usage around 60-75%. One thing you should make sure that you are not using multiple caching plugin. I have seen couple of users think using multiple caching plugin would provide better result, but probably it is a bad idea for your blog to mix up both caching algorithm and result a potential mess.

If you are running scheduled posts on your blog, then it is probably a better idea to run wp-cron.php using cronjobs. WordPress calls wp-cron.php each time a user comes into your blog which is fairly a stupid idea. I am not sure why wordpress does so, but calling it once a 2 hours seems enough. You can set the cronjobs from cpanel. To set the cronjobs every two hour, you would need to set the timing something similar to the following:

    0 */2 * * *

This would run at the very first minute of each even hours of the day. In the command section use something similar:

    php -q /home/cpanelusername/public_html/wp-cron.php

Replace cpanelusername with your original cpanel username. If you have added the blog as addon then probably, wp-cron.php is not in the public_html, but in a subfolder, so you would need to change the path accordingly, something similar to the following:

/home/cpanelusername/public_html/addondomain.com/wp-cron.php

A very well written article regarding the High CPU usage of wp-cron.php can be found here for your reference:

http://trinity777.wordpress.com/2008/10/28/wordpress-26-the-issue-of-wp-cronphp/

Two more interesting plugins which are frequently used by the clients can cause excessive CPU usage, they are “All in SEO Pack” and “Featured Gallery Plugin like Nextgen”. If you have no other option than using a gallery, then probably, you would have to stick with the Gallery, but I strongly suggest not to use all in seo pack. Using all these modules one by one is better than using this all in one plugin. A very well written article for WordPress SEO can be found here and I suggest you better read it before blindly installing All in one SEO pack:

http://yoast.com/articles/wordpress-seo/

A good percentage of users run autoblogs. Autoblogs are pretty popular in these days with wordpress. Autoblogs tends to take high CPU with their cron executions. There isn’t much you can do to reduce those certain high cpu usage time to time but a better idea to set the cronjobs at odd timing. For example setting the cron to run at 17 minutes of each hour may improve the performance instead of setting it at very first minute of the hour. Most of the users tend to use their crons at very first minute. It sometimes cause a little load issues when lots of cron tries to run at the same time. So using odd timing is truly a pretty decent idea for both parties. You should also find the best timing interval for your autoblog updates. A reasonable gap of 2-4 hours is always a better idea as it reduces the frequency of your cronjob. But if you have no other option than running it every hour, then just don’t think, put it for every hour :)

For any sort of additional help, please post a comment. We at Host SEO, provide absolute free consultation of reducing high CPU usage. Moreover, we would be pretty happy to install all the module and reconfigure your blog to make sure it takes less CPU and loads faster. So never hesitate to contact us for help :)