> On Fri, 25 Mar 2011, Andrew Doran wrote: > > > On Fri, Mar 25, 2011 at 12:16:32AM -0700, Erik Fair wrote: > > > > > It will be interesting to see if this class of problem shows up again when > > > NetBSD is supported on the UltraSPARC "Niagra" CPUs. > > > > Agree. Although as it stands 24 cores/threads would be a problem for > > sparc64 since it has a single mutex around the pmap. One of the goals of > > the uvmplock branch is to make it very easy to address that problem. > > The pmap needs to be rewritten for sun4v anyway since you can't access the > hardware directly any more.
i dunno about rewritten, but it needs some clean ups. FWIW, i've already made a bunch of removals of pmap_lock for sparc64 on the rmind-uvmplock branch (uncommited.) the clean up andy is talking about is pretty minor. there's more to go yet, and i haven't really benchmarked this at all yet, but the uvmplock branch definately seems more stable for the sparc* platforms than HEAD right now for SMP. it is however, not quite finished. .mrg.
