HTTP 503 message or my website is very slow or sluggish. How do I fix this?

First of all, we will briefly explain where HTTP 503 error messages or complaints about website slowness can come from. Your hosting package has a number of limits (CPU & RAM), we have set these limits so that a single customer cannot load an entire server to the point where other customers experience problems. Once a web hosting package runs into one of these limits, the server will display an HTTP 503 message or your website will slow down significantly to allow your package to 'cool down' temporarily. When this has returned to normal, your package will be released again. Below we are showing you how you can view your website resource usage.

Login on Plesk Control Panel

  1. In My Cloud86 (link), click in the left menu on My Services.
  2. Click the 3 dots behind the web hosting package you want to see in Plesk and click View Details.
  3. Under the heading Manage Webhosting (middle of the page), click on Websites & Domains.
  4. You will now be automatically logged into the Plesk Control Panel.

For the full manual with images, follow Login to Plesk

Display Resource Usage of my Web hosting Plan

  1. In Plesk, in the right menu click on Resource Usage.resource_verbruik.png
  2. On the next page, you already receive a message if you have reached a certain limit.

Understanding Resource Limits

The above message (Physical memory resources limit was reached for your site) means that the RAM memory (physical memory) limit of your hosting package has been reached resulting in a 503 message or a slow website. If you click on Current usage tab (or the blue Details button you can also see the specifics.


You see here that at about two times during the day, the physical memory limit of the package is reached. At these times you can experience a 503 message or notice that your website is a lot slower. This can have numerous causes such as an update you are doing to your website, a certain (cron) task that is running to update your products in your webshop for example. The fact is that there is something in your website, or a certain task that is running, that is causing you to reach your limit.

Note: It is good to realize that it is important, that you always optimize your website as much as possible. Poorly optimized websites can cause, even on the most comprehensive package, the hosting to run into limits.

So the usage of your hosting package depends not only on visitors, but when using WordPress, for example, the more plugins you use, the heavier the theme the greater the memory usage becomes. What we often see is that in the Web hosting Start package, our entry level package, a heavy plug-in like the WooCommerce shop is installed. The WooCommerce plug-in is unsuitable for the smallest hosting package. You will have to use at least our Webhosting Medium package for this, where you are much less likely to run into the limit of your RAM memory because the limits are set much wider.

If you experience the problem with HTTP 503 error messages often or your website is slow or sluggish with regularity, we recommend going through the points below:

  1. Important for resource optimization is caching, this can save quite a bit in memory usage. We recommend using the Litespeed caching plug-in for caching.
  2. Limit the number of plugins in your website, because the more plug-ins, the higher the memory usage. Delete unused plugins and deactivated plugins.
  3. Delete all unnecessary files (cache files, duplicate files, old backup files, etc.).
  4. Upgrade your hosting package, which therefore also gives you more resources and higher limits for your hosting package.

  5. If the possible solutions above do not help you, do not hesitate to contact us! And we can take a look and provide you with some advise.

If you need some help, you can always reach our support desk by email and on weekdays from 10:00 am to 4:00 pm you can also reach us by phone and via the chat in My Cloud86.