How is this possible?


Renowned Member
May 2, 2010
Bursa, Turkey, Turkey
I decided to upgrade ram from 4 GB to 8 GB as it was using %80 of ram. But after doubling it, it still uses %80 of ram. See screen shot please.


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Is the graph the ram display for the whole node or a particular VM?

If a VM which OS is running within the VM?
Do you have quest-agent installed?
it is same as PVE shows. I am sure if I give more ram, vm will use it very interesting.
Then it is down to what your running within the Windows VM.

I am guessing your running something like SQL or some other software that will make use of any available ram as cache, if your assigning it ram it will use it to increase performance in general.
Nothing you need to do, SQL will always use the ram available to it.

If you can spare the extra RAM for the VM leave it as it is, if you can't then take some back.

The more RAM it has the more it can cache and perform better than always reading from disk.
Your OS and SQL will still cache into RAM.

I’m not sure what your worrying about, ram is there to be used, no point forcing it not to cache in ram and lose performance.

If anything else needs ram the OS will take back the cache use and hand it over to another application that requires it.

Your best just leaving it along and letting SQL deal with its own ram use.

ZFS only has an effect on ram use on the node level not VM level.
Correct because it will use ram to cache, you don’t need to worry. Give it as much ram as you can afford to.

It will use that to cache and remove the load on the disks directly. RAM is there to be used.
In most modern OS RAM usage is not indicative of system being overloaded.
It used to be the case. But not anymore.
Nowadays an OS will use whatever ram is available to increase performance and will free up memory as needed for other apps and proceses on demand.


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