Memory & Cache Usage

[Joel_A]

Hello together

I have a smaller Centos server with 3 cores, 7 GB RAM and 10 GB swap (swap is on separate RAM and not HDD).

Maybe someone can enlighten me a little bit better here. Below is an excerpt or screenshot of htop. Everything basic is very familiar to me, except one:

The RAM load is just about 700M of 7G. The rest always seems to be used completely as a cache in a very short time. Even after a restart, it fills up completely in a few minutes.

This will surely have its reason, to save maybe writing performance, idk. The point is, with all my other hosts, also Centos with cPanel, this does not occur.

Why does this happen?
What exactly is this good for?
And is this even problematic?

Thank you for an explanation.

 

[GOT]

I'm surprised to hear you say that you dont see this with other cpanel centos servers. This is a universal behavior for linux. Linux maximizes ram usage by sticking recent data into soare memory. It's not uncommon for used+cached to hit 90% of ram utilization. Linux will dump this cache data if an application needs more ram This is all automatically controlled through the kenrel.

Definitely not problematic.

 

[cPanelMichael]

Hi @Joel_A,

In addition to the information @GOT provided, we also have a tutorial that helps explain this:

Tutorial - Understanding Memory Usage On Linux Operating Systems

Thank you.