Re: [Libvir] [PATCH] Implement memory operations for qemu driver
On Mon, Mar 17, 2008 at 04:21:04PM -0400, Cole Robinson wrote:
The attached patch implements the following operations for the qemu
driver:
virDomainGetMaxMemory
virDomainSetMaxMemory
virDomainSetMemory
The patch itself, +1.
Maybe we should investigate whether qemu/kvm does or will support a
way to dynamically set the memory of an active domain. (There is no
current support for this that I can see from the documentation).
A few questions/comments:
1) I changed maxmem and memory in the qemu_vm_def struct to unsigned long
to match the public api for memory values. Seems to work, but not sure
if there are any undesirable side effects to this.
It seems better as unsigned long, particularly for supporting 64 bit
archs with lots of memory.
2) Should SetMaxMem be able to be called on a running guest? This
code
allows it, since maxmem is basically a metavalue that doesn't directly
affect a guest.
3) Should maxmem be able to be set lower than the currently allocated mem?
This code does not allow this. If this changed, would also need to take
into account how we would handle this if we can change the maxmem while
the guest is running. After rethinking, we probably should be able to
do this, but I haven't changed the code.
As far as I understand what maxmem means (for Xen), this seems to be
correct behaviour.
Rich.
--
Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones
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