On Mon, Dec 05, 2011 at 12:29:25AM +0000, Mindaugas Rasiukevicius wrote: > "Chuck Silvers" <c...@netbsd.org> wrote: > > Module Name: src > > Committed By: chs > > Date: Sun Dec 4 16:24:13 UTC 2011 > > > > Modified Files: > > src/sys/arch/amd64/amd64: locore.S machdep.c > > src/sys/arch/amd64/include: types.h > > src/sys/arch/x86/include: pmap.h > > src/sys/arch/x86/x86: pmap.c > > > > Log Message: > > map all of physical memory using large pages. > > ported from openbsd years ago by Murray Armfield, > > updated for changes since then by me. > > This is cool, thanks! Can you add an entry to src/doc/CHANGES? Also, > just wondering - did you try any benchmarks? I would expect reasonable > improvement.
does it really make sense to list incremental performance improvements there? I can add it if folks want, but we don't tend to document misc performance improvements that have no API impact outside the kernel. as for how much it helps, on a 12-CPU box "build.sh release" is about 2.5% faster. if I enable __HAVE_CPU_UAREA_ROUTINES so that uareas are also accessed this way that gives an additional 0.5% speedup. coincidentally, this almost exactly compensates for the performance hit of enabling DIAGNOSTIC. -Chuck