Re: [Qemu-devel] KVM "fake DAX" device flushing

[Dan Williams]

On Thu, May 11, 2017 at 11:17 AM, Stefan Hajnoczi <address@hidden> wrote:
> On Wed, May 10, 2017 at 09:26:00PM +0530, Pankaj Gupta wrote:
>> We are sharing initial project proposal for
>> 'KVM "fake DAX" device flushing' project for feedback.
>> Got the idea during discussion with 'Rik van Riel'.
>
> CCing NVDIMM folks.
>
>>
>> Also, request answers to 'Questions' section.
>>
>> Abstract :
>> ----------
>> Project idea is to use fake persistent memory with direct
>> access(DAX) in virtual machines. Overall goal of project
>> is to increase the number of virtual machines that can be
>> run on a physical machine, in order to increase the density
>> of customer virtual machines.
>>
>> The idea is to avoid the guest page cache, and minimize the
>> memory footprint of virtual machines. By presenting a disk
>> image as a nvdimm direct access (DAX) memory region in a
>> virtual machine, the guest OS can avoid using page cache
>> memory for most file accesses.

How is this different than the solution that Clear Containers came up with?

https://lwn.net/Articles/644675/