On Sun, Dec 24, 2017 at 09:12:56AM +0000, Richard Sandiford wrote: > Segher Boessenkool <seg...@kernel.crashing.org> writes: > > On Fri, Dec 22, 2017 at 04:53:47PM -0600, David Esparza wrote: > >> With a value of 85 GCC has a CPU performance degradation of 11%, > >> reverting PRED_LOOP_EXIT to 92 this degradation disappear. > >> Those values where measured by running c-ray ray-tracer that is a > >> floating point benchmark that runs out of L1 cache. > > > > Why is this single benchmark more important than everything else? > > > > https://patchwork.ozlabs.org/patch/637073/ > > "Everything" else? :-) It sounds from Andrew's reply like it wasn't > a win on other benchmarks too.
Yeah... But at least Martin tested spec2006, instead of one single tiny non-representative program. > Neither covering message has really explained why the previous value was > too low/high, but maybe that's just the way it goes with these tuning > parameters... It would be nice if they explained how they tested things. Segher
