On 22.11.19 16:53, Christopher Lameter wrote: > On Fri, 22 Nov 2019, Pengfei Li wrote: > >> I am sorry that I did not make it clear. I want to express this series >> of patches will benefit NUMA systems with multiple nodes. > > Ok but that benefit needs to be quantified somehow. > >> The main benefit is that it will be more efficient when traversing all >> nodes (for example when performing page reclamation). > > And you loose the prioritization of allocations through these different > zones. We create zonelists with a certain sequence of the zones in > order to prefer allocations from certain zones. This is in particular > important for the smaller DMA zones which may be easily exhausted. > That's an important point also when MOVABLE is in place. You really don't want to go to random other zones before considering all MOVABLE zones. Same with DMA and NORMAL. -- Thanks, David / dhildenb
