> 04bac040bc71b4b3 5649d113ffce9f532a9ecc5ab96 > ---------------- --------------------------- > %stddev %change %stddev > \ | \ > 10026093 ± 3% -33.1% 6702748 ± 2% vm-scalability.throughput I try to reproduce this and see vm-scalability.throughput really decrease. And I use ftrace found that functions related to this patch add_to_swap_cache()/__delete_from_swap_cache()/clear_shadow_from_swap_cache() consume more time while workingset_update_node() be called much more times. Since the patch result in consuming much more resource, and the problem this patch try to solve is not apparent to user, we may abandon this patch. By the way, as what this test result shows, mapping_set_update() should also consume much time. Should we care about this? Thanks. Reproduce before this patch: /vm-scalability-master # cat /sys/kernel/debug/tracing/trace_stat/function0 Function Hit Time Avg s^2 -------- --- ---- --- --- add_to_swap_cache 26108 476290.6 us 18.243 us 487.762 us __delete_from_swap_cache 26117 462492.6 us 17.708 us 77.801 us clear_shadow_from_swap_cache 27840 199925.1 us 7.181 us 313.126 us Reproduce after this patch: /vm-scalability-master # cat /sys/kernel/debug/tracing/trace_stat/function* Function Hit Time Avg s^2 -------- --- ---- --- --- add_to_swap_cache 51268 1371819 us 26.757 us 676.311 us __delete_from_swap_cache 51260 1322712 us 25.803 us 123.010 us workingset_update_node 157455 770064.9 us 4.890 us 15.108 us clear_shadow_from_swap_cache 52928 563597.4 us 10.648 us 199.766 us
