DirectAdmin Resource Usage and performance problems (Resource Limit Is Reached)
In the DirectAdmin control panel you will find the Resource Usage option at the bottom. Here you can see how the CPU usage and number of processes of your hosting package develop over time. Monitoring these limits is necessary with shared hosting, because you share the server with other users/websites. This largely allows us to prevent 1 website from taking too many resources, which would then affect other websites on the same server.
Some large/heavy websites (such as online shops) need more computing power than other websites even under normal use. If you are confident that the site is working correctly, the information below does not apply. In that case, one option is to upgrade to a more powerful hosting package with more computing power. View our hosting packages here. This article explains more about the possible causes of high usage.
A short explanation of how this works.
How it works
With a Linux hosting package you are allocated a certain part of a shared hosting server. Within that part you essentially run completely independently: if another website demands too much CPU or too many processes, it will in principle not affect you, and vice versa. However, if your own site performs poorly, you will be the one who suffers. The available resources are normally more than sufficient to run a website well. But if the website does not work properly, for example scripts that do not access the database efficiently, this can
cause such problems and may even result in your site no longer being accessible at all, or only poorly.
Multiple domains in 1 hosting package
This mechanism works per hosting package, so if you have several domains in one hosting package, the chance of reaching these limits is greater. So give a domain that needs to perform well its own hosting package, so that it can never be affected by the other domains in a hosting package.
CPU Usage
The CPU usage graph shows how the site behaves. You can view this for up to 30 days back. If your site is already high in the graph with only a few users, you can be almost certain that you will run into performance problems with your site as the number of users increases. Keep a close eye on this so that you can take action yourself in time. This is also recommended if you use standard scripts. If you add plugins/modules to these standard scripts, a single such module can be enough to make the speed collapse. So check this regularly, especially if you have changed something on your site. Pay close attention to the aCPU column, which shows the average; mCpu shows the peaks. If there are peaks of almost 100%, it is worth tracking them down now, before they cause problems.
Memory Usage
This limit is only rarely exceeded. If it is, you can be fairly sure that something is not put together properly, causing it to use too much memory.
Entry Processes
Combined with CPU usage, this is crucial. The number of entry processes shows how many processes have been active for your site at the same time (this is not the same as the number of visitors; 1 process can serve many visitors). When the limit is reached, the website will show a 404 error with the text 'The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.'. If this did not happen, it could endanger the entire server and possibly bring it down. The combination of CPU and processes is therefore very important. If a script causes high CPU usage, the process will take longer to complete and the maximum number of users will also drop quickly. We sometimes see sites collapse with 10 users while other sites with thousands of users keep running quickly without any problems.
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Input/Output usage
Every website that is displayed has to be read from the server's disks. We call this input/output. To display reasonably quickly, a website should normally never be larger than 0.5 or 1 MB. A maximum of 3 MB per second has been set for reading from or writing to disk. This too is a generous limit and normally sufficient. If you hit these limits, there is a good chance that the website itself is already too large or that it writes (too) much to disk. Switching plugins on or off in scripts such as Joomla/WordPress can have a big effect on this. When the limit is reached, there may be delays when displaying, opening or working with the site.
Deactivating the domain and then reactivating it
To let your domain settle down, you can request a list of your domains in domain management, tick the domain concerned (or all of them) and then click Suspend at the bottom. Leave the domain deactivated for about ten minutes and then activate it again. There is a good chance it will then come back online normally, but it is also quite likely that this will happen again.