Hi,
When I tried to evaluate the performances of my servers, I am confused by a memory usage problem.
I feel that the VMware memory balloon technique could explain this, but I wish my assumption is correct.
All my servers are installed on a VMware and they are linux centos 7.
This is the memory of one of my servers observed from vcenter.
While after console into this centos7 and check memory from there, it shows the memory usage is 97%
I tried to calculate memory usage by myself via
i realized the memory usage could not be 97% and the figure shown from vcenter is correct.
But how can the command "sar" shows the memory usage is about 97% ?
I guess VMware does not allocate the full memory to this client (I give 6G to this server when creating) and it only provides a little bit more than what this servers is actually needed. That is why Sar shows the memory usage is always above 90%.
The 6G is actually of the ceiling of memory that vmware host is able to allocate to this client.
Could experts justify my assumption?
Regards
Michael