Re: [linux-next:master] [mm] 1111d46b5c: stress-ng.pthread.ops_per_sec -84.3% regression

Yin, Fengwei
2023-12-21T13:40:19Z

On 12/21/2023 8:58 AM, Yin Fengwei wrote:
> But what I am not sure was whether it's worthy to do such kind of change
> as the regression only is seen obviously in micro-benchmark. No evidence
> showed the other regressionsin this report is related with madvise. At
> least from the perf statstics. Need to check more on stream/ramspeed.
> Thanks.

With debugging patch (filter out the stack mapping from THP aligned),
the result of stream can be restored to around 2%:

commit:
30749e6fbb3d391a7939ac347e9612afe8c26e94
1111d46b5cbad57486e7a3fab75888accac2f072
89f60532d82b9ecd39303a74589f76e4758f176f -> 1111d46b5cbad with
debugging patch

30749e6fbb3d391a 1111d46b5cbad57486e7a3fab75 89f60532d82b9ecd39303a74589
---------------- --------------------------- ---------------------------
350993 -15.6% 296081 ± 2% -1.5% 345689
stream.add_bandwidth_MBps
349830 -16.1% 293492 ± 2% -2.3% 341860 ±
2% stream.add_bandwidth_MBps_harmonicMean
333973 -20.5% 265439 ± 3% -1.7% 328403
stream.copy_bandwidth_MBps
332930 -21.7% 260548 ± 3% -2.5% 324711 ±
2% stream.copy_bandwidth_MBps_harmonicMean
302788 -16.2% 253817 ± 2% -1.4% 298421
stream.scale_bandwidth_MBps
302157 -17.1% 250577 ± 2% -2.0% 296054
stream.scale_bandwidth_MBps_harmonicMean
339047 -12.1% 298061 -1.4% 334206
stream.triad_bandwidth_MBps
338186 -12.4% 296218 -2.0% 331469
stream.triad_bandwidth_MBps_harmonicMean

The regression of ramspeed is still there.

Regards
Yin, Fengwei