Chuck Silvers <c...@chuq.com> wrote: > > > 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.
Yes, we should and do list such changes. Also, 2.5% is quite good and it is useful to collect such numbers in doc/CHANGES for marketing purposes. > 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. Cool! Any reason why __HAVE_CPU_UAREA_ROUTINES is not enabled by default? > coincidentally, this almost exactly compensates for the performance hit > of enabling DIAGNOSTIC. It really depends on the workload, e.g. effects on sysbench OLTP are quite visible or e.g. PR/45734. > > -Chuck -- Mindaugas
