CentOS 5.7 dedicated server. No memory intensive processes running. 12GB RAM installed.
Mem: 12462256k total, 12425344k used, 36912k free, 395528k buffers Swap: 1999864k total, 344k used, 1999520k free, 10795472k cached
I contacted our server provider and they said:
The cached content is about 10 GB and this is information that is often accessed by the system, this way the server is able to faster access it when the information is needed. This information can always be freed and memory to be allocated for other needs.
Does that make sense?
I checked another server with only 4GB of RAM. It's also "doing nothing" but sure enough has 99% of RAM marked as "used". But in that case very little of it is marked as "cached".
Mem: 3969436k total, 3945568k used, 23868k free, 352740k buffers Swap: 2097144k total, 1206984k used, 890160k free, 53232k cached
Can anyone make sense of this?