Re: [v2 RFC PATCH 0/9] Another Approach to Use PMEM as NUMA Node

From: Dave Hansen
Date: Tue Apr 16 2019 - 19:04:26 EST


On 4/16/19 2:59 PM, Yang Shi wrote:
> On 4/16/19 2:22 PM, Dave Hansen wrote:
>> Keith Busch had a set of patches to let you specify the demotion order
>> via sysfs for fun. The rules we came up with were:
>> 1. Pages keep no history of where they have been
>> 2. Each node can only demote to one other node
>
> Does this mean any remote node? Or just DRAM to PMEM, but remote PMEM
> might be ok?

In Keith's code, I don't think we differentiated. We let any node
demote to any other node you want, as long as it follows the cycle rule.