Ok. So that's why I was getting 1 GB as a result. So is there any way I can get memory in used programmatically? I mean without going inside guest domain. On Aug 5, 2016 5:42 PM, "Andrea Bolognani" <abologna@redhat.com> wrote:
On Thu, 2016-08-04 at 20:02 +0500, Aleem Akhtar wrote:
I am trying to get stats of Domains running under XEN hypervisor. I used Libvirt function for this purpose. I am trying to understand output for Memory. Domain running is Fedora-22 with 1GB Ram. Here is my code
y = virDomainGetInfo(allDomain, &info); if (y == -1) printf("Errorl\n"); else { printf("Max Memory: %lu\n", info.maxMem); printf("Memory: %lu", info.memory); }
I get output as
Max Memory: 1048576 Memory: 1048576
Now, as per Libvirt API, info.memory should return the memory in KBytes used by the domain. My Question is, if info.memory returns memory used and my domain is using complete 100% of Max Memory or not? Also I tried to create Domain with memory varying from 128MB to 2GB with same effect. I also tried to run some applications in Domain but Memory usage return by given function does not change. Any help or guidance will be much appreciated.
The relevant virDomainInfo field is described as
/* the memory in KBytes used by the domain */ unsigned long memory;
but in this context, "used by" really means "available to".
So the output above tells you that your Fedora guest has 1 GB of memory available; how much of that memory is actually being used by the guest OS is something that you can find out by running top inside the guest.
-- Andrea Bolognani / Red Hat / Virtualization