And on an experiment in spectral identification that mainly does F64
inner products, I get with the default build
(time (run-experiment-and-graph 5)) 785617 ms real time 785590 ms cpu time (785040 user, 550 system) 33 collections accounting for 442 ms real time (350 user, 80 system) 3216061748 bytes allocated 30338 minor faults no major faults
and with the gcc-4.8 build I get
(time (run-experiment-and-graph 5))
(time (run-experiment-and-graph 5)) 739829 ms real time 739790 ms cpu time (739620 user, 170 system) 33 collections accounting for 292 ms real time (310 user, 0 system) 3216060588 bytes allocated 17663 minor faults no major faults
using -fstrict-aliasing didn’t help the spectral identification code much:
(time (run-experiment-and-graph 5))
(time (run-experiment-and-graph 5)) 733849 ms real time 733750 ms cpu time (733330 user, 420 system) 33 collections accounting for 219 ms real time (210 user, 0 system) 3216086556 bytes allocated 16938 minor faults no major faults
Awesome project! Raspberry Pi is truly a wonderful machine. Thank you for posting your results. Since I don't have a reference performance, is this 20x difference expected or more than expected? Based on other tests with very different environments on mobile ARM, I would say that it should be on the 10x-50x ballpark.