On 4/16/19 4:04 PM, Dave Hansen wrote:
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.
I recall Keith's code let the userspace define the target node. Anyway,
we may need add one rule: not migrate-on-reclaim from PMEM node.
Demoting from PMEM to DRAM sounds pointless.
