Re: [RFC] Memory Tiering

[Verma, Vishal L]

On Thu, 2019-10-17 at 07:17 -0700, Dave Hansen wrote:
> On 10/17/19 1:07 AM, David Hildenbrand wrote:
> > Very interesting topic. I heard similar demand from HPC folks 
> > (especially involving other memory types ("tiers")). There, I think
> > you often want to let the application manage that. But of course, for
> > many applications an automatic management might already be
> > beneficial.
> > 
> > Am I correct that you are using PMEM in this area along with
> > ZONE_DEVICE and not by giving PMEM to the buddy (add_memory())?
> 
> The PMEM starts out as ZONE_DEVICE, but we unbind it from its original
> driver and bind it to this stub of a "driver": drivers/dax/kmem.c which
> uses add_memory() on it.
> 
> There's some nice tooling inside the daxctl component of ndctl to do all
> the sysfs magic to make this happen.
> 
Here is more info about the daxctl command in question:

https://pmem.io/ndctl/daxctl-reconfigure-device.html