wesupport

Need help?

Our experts have had an average response time of 13.14 minutes in February 2024 to fix urgent issues.

We will keep your servers stable, secure, and fast at all times for one fixed price.

What is “OOM killed process httpd” and how to resolve it in OpenVZ or Virtuozzo VPS servers

by | Jun 23, 2015

In our role as Outsourced Tech Support for web hosts, VPS customers hosted in OpenVZ or Virtuozzo servers often report their sites crashing with the error OOM killed process httpd.

It often happens with high traffic websites or with sites hosted in starter plans. Today we’ll discuss what this error means and how we fix it for our customers.

[ You don’t have to lose your sleep to keep your customers happy. Our Hosting Support Specialists cover your servers and support your customers 24/7 at just $9.99/hour. ]

What is meant by OOM errors?

OOM is short for Out Of Memory manager. It is a kernel mechanism in server virtualization systems to save the VPS when the available memory becomes too low.

Linux kernel by default gives every httpd process whatever memory it asks for, with the assumption that not all processes are going to use it. However, in high traffic websites, the number of such processes becomes too high and uses up almost all the memory in the VPS.

Then the OOM manager activates and kills off processes with a high oom_score value (calculated based on the process’s memory usage and its priority).

Now, let’s map this to some actual VPS settings. If the VPS uses SLM memory, the guaranteed amount of RAM for the container is set by the “soft limit” memory setting and the burstable RAM is set by the “hard limit” memory setting.

Let’s say the VPS has the following memory setting.

soft limit = 512
hard limit = 1024

This means the kernel will lay low until the actual memory usage exceeds 512 MB. After that limit, as the memory usage approaches 1024 MB, OOM gets activated, and starts killing the httpd processes.

[ Running a hosting business doesn’t have to be hard, or costly. Get world class Hosting Support Specialists at $9.99/hour (bulk discounts available) ]

Resolving OOM errors

Un-optimized websites are the top reason for this error. Website issues could be caused by poorly coded plugins or un-optimized custom website code. Another reason is a surge in website traffic, either due to a marketing campaign, or due to DoS attacks.

If the usage is legitimate, the solution is to increase the memory. If it is not, the solution is to implement Web Application Firewalls, or remove un-optimized sections of the website.

[ Use your time to build your business. We’ll take care of your customers. Hire Our Hosting Support Specialists at $9.99/hr. ]

Are you looking for expert technical support for your VPS systems? If you’d like know more about how our 24/7 hosting support can help your business, feel free to contact us.

 

STOP SPENDING TIME ON SUPPORT!

Do you spend all day answering technical support queries?

Wish you had more time to focus on your business? Let us help you.

We free up your time by taking care of your customers and servers. Our engineers monitor your servers 24/7, and support your customers over help desk, live chat and phone.

HIRE SUPPORT SPECIALISTS AT $9.99/HR

0 Comments

Categories

Tags