when I read something about overcommitting of Virtual Machines (https://docs.fedoraproject.org/en-US/Fedora/18/html/Virtualization_Administration_Guide/sect-Virtualization-Tips_and_tricks-Overcommitting_with_KVM.html), I have some some questions.
At first, my host computer system is like below 1.Memory(DRAM) : 16GB 2.swapspace(swap partition) : 32GB 3.SSD : 512GB
I installed KVM and made my Virtual Machine(VM). my VM setting is 1.Memory : 4GB 2.swapspace(swap partition) : 8GB 3.virtual Disk capacity : 20GB
If I limit memory resource of VM from 4GB to 1GB by cgroup interface, it would be overcommitment situation if my VM's memory footprint is more than 1GB.
In this Url, (https://unix.stackexchange.com/questions/137509/kvm-and-swap-space) in Memory overcommit situation, VM will use swap-space(swap-partition) as a memory.
Because I limited memory resource of my VM to 1GB, I hoped my VM will use swap-space as a memory and I hoped I could see some swapout situation on my host OS when my VM use more than 1GB memory. \ But I couldn't.
some swap-out(so) happened but, very small relative to Block-I/O(bo). Block I/O means it(VM) is submitting I/O to device file not swap-space(swap-file). It seems it doesn't use swap-space as a memory. It seems it is just writeback dirty caches because they just have only 1GB memory. Is there any part I am missing?