On 08/08/16 13:44, Aldemir Akpinar wrote:
>

>     Sun, Aug 07, 2016 at 06:31:10PM +0200, Edward Bartolo wrote:

>

>     On the other hand, full-machine virtualization costs you the max of
>     assigned
>     memory to that system, at all time.

>
>
> Going off-topic but I just wanted to correct this statement, when you're
> using full machine virtualization in the worst case it will use all the
> memory assigned to the server (unless you're using xen). Products like
> vmware or hyper-v uses in memory deduplication and swapping the virtual
> machine files to the disk to reduce the memory usage.

Just for the record, so does KVM if you turn on ksm. It actually works
very well for a free solution.

This is a tiny array of linux & windows VMs (5 linux / 3 windows). ksm
effectively saves half the memory footprint.

root@srv:~# ./ksmstat2
Shared memory is 488 MB
Saved memory is 6557 MB
Shared pages usage ratio is 13.43
Unshared pages usage ratio is .95

Sure, not as efficient as any of the containers, but then the containers
can't run a blackberry BES or any of the other horrid windows software
you sometimes have to run as part of day to day business life catering
for others.