Question Linux memory cache keeps getting higher is this normal?

[bramokki]

Server operating system version

Ubuntu 20.04.6 LTS

Plesk version and microupdate number

v18.0.52

Few weeks ago i bought a new dedicated server switched from a vps with plesk. I migrated my websites using the plesk migrator.
On the last vps the cached ram was never getting higher than 2gb on a 16gb system. Now i have a 64gb ddr5 and every day the cached ram seems to get higher.
Sometimes adds 4gb when plesk makes a back-up. My question is will this be a problem? when i restart plesk all the cache is gone.
I used to have this issue few years back too where the cached memory was getting to high using cyberpanel. I only had 1 woocommerce website and the server would shutdown until i emptied the cache. Switched to a vps with plesk never had the issues again. One vps also had this issue until i reinstalled plesk completely from scratch and i would manually import my wordpress website. I am trying to figure out what the problem is and if i should reinstall plesk again? i already tried using the repair kit but did this not fix the issue.

 

[Peter Debik]

Help! Linux ate my RAM!

 

[bramokki]

Thanks, on last vps the same website and plesk did not use that much cached memory so i thought it might be a configuration problem.
And since with other panels the server crashed. I will just wait till it hits 100% cached memory and see what happens.

 

[mow]

Thanks, on last vps the same website and plesk did not use that much cached memory so i thought it might be a configuration problem.
And since with other panels the server crashed. I will just wait till it hits 100% cached memory and see what happens.

You won't see that on a vps because this layer of caching will be done on the physical host.

 

[bramokki]

Okay i understand because this showed (also cached) on the vps

 

[mow]

That may be, but the vps host will still use all otherwise unused ram for caching. How exactly it is assigned depends on whether you have a separate device/filesystem for your vps or it lives within the host filesystem. If you have a separate physical device passed through to your vps, there may be more cache used inside the vps than with a device the host manages itself.

 

[bramokki]

Hmm okay i just remember 2 years ago i had a vps with not that much ram only 2gb and the server would crash when it hit too much cached memory.
With the same website. I don't want it to happen again. But if this is normal i will just wait it out till it hits 100% and see what happens. Since every time there is a scheduled plesk back-up it adds 3gb cached ram.