On Sat, 2021-07-03 at 17:47 +0200, Mike Galbraith wrote: > On Sat, 2021-07-03 at 09:24 +0200, Mike Galbraith wrote: > > It also appears to be saying that there's something RT specific to > > stare at in addition to the list_lock business. > > The what is ___slab_alloc() consuming 3.9% CPU in tip-rt-slub whereas > it consumes < 1% in both tip-rt (sans slub patches) and tip-slub. > > The why remains to ponder. Ignoring odd distribution in the profile (red herring whackable via prefetch games), and removing perf/debug options from the picture, the remaining RT specific cost is just that of forced slow path. For hackbench in my little box, it adds up to right at 3%. -Mike
