On Wed 17-04-19 09:37:39, Keith Busch wrote: > On Wed, Apr 17, 2019 at 05:39:23PM +0200, Michal Hocko wrote: > > On Wed 17-04-19 09:23:46, Keith Busch wrote: > > > On Wed, Apr 17, 2019 at 11:23:18AM +0200, Michal Hocko wrote: > > > > On Tue 16-04-19 14:22:33, 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: > > > > > > > > I am not a fan of any sysfs "fun" > > > > > > I'm hung up on the user facing interface, but there should be some way a > > > user decides if a memory node is or is not a migrate target, right? > > > > Why? Or to put it differently, why do we have to start with a user > > interface at this stage when we actually barely have any real usecases > > out there? > > The use case is an alternative to swap, right? The user has to decide > which storage is the swap target, so operating in the same spirit. I do not follow. If you use rebalancing you can still deplete the memory and end up in a swap storage. If you want to reclaim/swap rather than rebalance then you do not enable rebalancing (by node_reclaim or similar mechanism). -- Michal Hocko SUSE Labs
