On Tue, Sep 14, 2021 at 08:40:38PM +1000, Michael Ellerman wrote: > Peter Zijlstra <pet...@infradead.org> writes:
> > I'm thinking we ought to keep hops as steps along the NUMA fabric, with > > 0 hops being the local node. That only gets us: > > > > L2, remote=0, hops=HOPS_0 -- our L2 > > L2, remote=1, hops=HOPS_0 -- L2 on the local node but not ours > > L2, remote=1, hops!=HOPS_0 -- L2 on a remote node > > Hmm. I'm not sure about tying it directly to NUMA hops. I worry we're > going to see more and more systems where there's a hierarchy within the > chip/package, in addition to the traditional NUMA hierarchy. > > Although then I guess it becomes a question of what exactly is a NUMA > hop, maybe the answer is that on those future systems those > intra-chip/package hops should be represented as NUMA hops. > > It's not like we have a hard definition of what a NUMA hop is? Not really, typically whatever the BIOS/DT/whatever tables tell us. I think in case of Power you're mostly making things up in software :-) But yeah, I think we have plenty wriggle room there.
