Re: [RFC 0/2] kvm: Transcendent Memory (tmem) on KVM

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Thu, Mar 08, 2012 at 09:59:41PM +0530, Akshay Karle wrote:
> Hi,
> 
> We are undergraduate engineering students of Maharashtra Academy of
> Engineering, Pune, India and we are working on a project entitled
> 'Transcendent Memory on KVM' as a part of our academics.
> The project members are:
> 1. Ashutosh Tripathi
> 2. Shreyas Mahure
> 3. Nishant Gulhane
> 4. Akshay Karle
> 
> ---
> Project Description:
> What is Transcendent Memory(tmem in short)?
> Transcendent Memory is a memory optimization technique for the
> virtualized environment. It collects the underutilized memory of the
> guests and the unassigned(fallow) memory of the host and places it into
> a central tmem pool. Indirect access to this pool is then provided to the guests.
> For further information on tmem, please refer the article on lwn by Dr.
> Dan Magenheimer:
> http://lwn.net/Articles/454795/
> 
> Since kvm is one of the most popular hypervisors available,
> we decided to implement this technique for kvm.
> 
> ---
> kvm-tmem Patch details:
> This patch adds appropriate shims at the guest that invokes the kvm
> hypercalls, and the host uses zcache pools to implement the required
> functions.

Great!

> 
> To enable tmem on the 'kvm host' add the boot parameter:
> "kvmtmem"
> And to enable tmem in the 'kvm guests' add the boot parameter:
> "tmem"
> 
> The diffstat details for this patch are given below:
>  arch/x86/include/asm/kvm_host.h      |    1 
>  arch/x86/kvm/x86.c                   |    4 
>  drivers/staging/zcache/Makefile      |    2 
>  drivers/staging/zcache/kvm-tmem.c    |  356 +++++++++++++++++++++++++++++++++++
>  drivers/staging/zcache/kvm-tmem.h    |   55 +++++
>  drivers/staging/zcache/zcache-main.c |   98 ++++++++-
>  include/linux/kvm_para.h             |    1 
>  7 files changed, 508 insertions(+), 9 deletions(-)
> 	
> We have already uploaded our work alongwith the 'Frontswap' submitted by Dan,
> on the following link:
> https://github.com/akshaykarle/kvm-tmem
> 
> Any comments/feedback would be appreciated and will help us a lot with our work.

Great. Will do.
> 
> Regards,
> Akshay