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Re: [patch] Make prefetching parameters controlable with --param
Hello,
> Presumably the new k8 value of 100 simultaneous prefetches (a significant
> increase from the previous value of 6) has demonstrable advantages for
> some benchmark?
here are the results of stream benchmark (-O2 -march=k8
-fprefetch-loop-arrays):
before:
Function Rate (MB/s) Avg time Min time Max time
Copy: 2290.1313 0.0140 0.0140 0.0140
Scale: 2244.8565 0.0143 0.0143 0.0143
Add: 2482.1733 0.0194 0.0193 0.0194
Triad: 2432.7146 0.0197 0.0197 0.0198
after:
Function Rate (MB/s) Avg time Min time Max time
Copy: 2375.4509 0.0135 0.0135 0.0135
Scale: 2323.3923 0.0139 0.0138 0.0148
Add: 2642.0119 0.0182 0.0182 0.0182
Triad: 2597.6954 0.0186 0.0185 0.0191
(the improvements are consistent over several runs).
Zdenek