On Wed, Feb 08, 2023 at 01:05:28PM +0530, Bharata B Rao wrote: > - Perf uses IBS and we are using the same IBS for access profiling here. > There needs to be a proper way to make the use mutually exclusive. No, IFF this lives it needs to use in-kernel perf. > - Is tying this up with NUMA balancing a reasonable approach or > should we look at a completely new approach? Is it giving sufficient win to be worth it, afaict it doesn't come even close to justifying it. > - Hardware provided access information could be very useful for driving > hot page promotion in tiered memory systems. Need to check if this > requires different tuning/heuristics apart from what NUMA balancing > already does. I think Huang Ying looked at that from the Intel POV and I think the conclusion was that it doesn't really work out. What you need is frequency information, but the PMU doesn't really give you that. You need to process a *ton* of PMU data in-kernel.
