CentOS virt - Feb 2013 - Virtualisation, guests cached memory and density

Hello,

We all know linux distros will use most of the free memory available 
for caching stuff, I/O buffers etc (hence sites like linuxatemyram.com).
In many virt scenarios we have some sort of memory deduplication 
mechanisms, such as KSM on KVM (don't know how it's called in Vmware).

My situation is one where I need to cram up as many virtual machines as 
I can on a single hypervisor and I believe KSM does not work for the 
memory used as cache/buffers.
How could I work around this? Any other pointers for achieving higher 
density welcome (don't suggest container technology please).

-- 
Sent from the Delta quadrant using Borg technology!

Nux!
www.nux.ro

On 02/08/2013 11:26 AM, Nux! wrote:
> How could I work around this? Any other pointers for achieving higher 
> density welcome (don't suggest container technology please).
Xen, because of the way it works, will always get to higher density /
performance than KVM when desity and reasonable performance are on the
plate.


Regards

- KB

-- 
Karanbir Singh
+44-207-0999389 | http://www.karan.org/ | twitter.com/kbsingh
GnuPG Key : http://www.karan.org/publickey.asc

On Fri, 8 Feb 2013, Karanbir Singh wrote:
> Xen, because of the way it works, will always get to higher density /
> performance than KVM when desity and reasonable performance are on the
> plate.
My experience is the exact opposite.

-s

On 02/08/2013 05:20 PM, Steve Thompson wrote:
> On Fri, 8 Feb 2013, Karanbir Singh wrote:
>> Xen, because of the way it works, will always get to higher density /
>> performance than KVM when desity and reasonable performance are on the
>> plate.
> 
> My experience is the exact opposite.
Do tell more..

- KB

-- 
Karanbir Singh
+44-207-0999389 | http://www.karan.org/ | twitter.com/kbsingh
GnuPG Key : http://www.karan.org/publickey.asc

> How could I work around this? Any other pointers for achieving higher?
> density welcome (don't suggest container technology please).
See memory ballooning.