Hi Mel, I applied your patchset on v3.13-rc7 and get some test results. The results are encouraging: hackbench throughput increased by 34.7% with parameters 1600%-threads-pipe on a 2S SNB server. In case you are interested, here are the full list of changes. kconfig is attached. v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 171792 ~ 0% +34.7% 231378 lkp-snb01/micro/hackbench/1600%-threads-pipe 171792 +34.7% 231378 TOTAL hackbench.throughput v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 2296537 ~ 1% -100.0% 5 grantley/micro/kbuild/200% 291546 ~ 0% +1.3e+14% 3.85e+17 lkp-a04/micro/netperf/120s-200%-TCP_CRR 96565 ~ 0% -100.0% 0 lkp-a04/micro/netperf/120s-200%-TCP_MAERTS 97525 ~ 1% +1.7e+14% 1.692e+17 lkp-a04/micro/netperf/120s-200%-TCP_RR 97140 ~ 0% +1.8e+16% 1.76e+19 lkp-a04/micro/netperf/120s-200%-TCP_SENDFILE 97303 ~ 0% -100.0% 0 lkp-a04/micro/netperf/120s-200%-UDP_RR 6294840 ~ 2% +4.2e+12% 2.617e+17 ~ 3% lkp-snb01/micro/hackbench/1600%-process-pipe 1384593 ~ 1% +6.9e+12% 9.551e+16 lkp-snb01/micro/hackbench/1600%-threads-pipe 1119351 ~ 2% +1.8e+13% 2.038e+17 lkp-snb01/micro/hackbench/1600%-threads-socket 186442 ~ 0% +3.5e+13% 6.473e+16 ~ 0% xps2/micro/pigz/100% 11961847 +1.6e+14% 1.878e+19 TOTAL proc-vmstat.nr_tlb_local_flush_one v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 150 ~ 4% +2.6e+17% 3.85e+17 lkp-a04/micro/netperf/120s-200%-TCP_CRR 153 ~ 5% -100.0% 0 lkp-a04/micro/netperf/120s-200%-TCP_MAERTS 148 ~ 5% +1.1e+17% 1.692e+17 lkp-a04/micro/netperf/120s-200%-TCP_RR 153 ~ 3% +1.1e+13% 1.679e+13 lkp-a04/micro/netperf/120s-200%-TCP_SENDFILE 154 ~ 5% -100.0% 0 lkp-a04/micro/netperf/120s-200%-UDP_RR 24275 ~12% +5.6e+14% 1.361e+17 lkp-snb01/micro/hackbench/1600%-threads-pipe 25035 +2.8e+15% 6.903e+17 TOTAL proc-vmstat.nr_tlb_remote_flush v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 215 ~ 4% +1.8e+17% 3.85e+17 lkp-a04/micro/netperf/120s-200%-TCP_CRR 222 ~ 4% -100.0% 0 lkp-a04/micro/netperf/120s-200%-TCP_MAERTS 213 ~ 3% +7.9e+16% 1.692e+17 lkp-a04/micro/netperf/120s-200%-TCP_RR 221 ~ 3% +7.9e+18% 1.76e+19 lkp-a04/micro/netperf/120s-200%-TCP_SENDFILE 221 ~ 3% -100.0% 0 lkp-a04/micro/netperf/120s-200%-UDP_RR 275020 ~16% +6e+13% 1.663e+17 lkp-snb01/micro/hackbench/1600%-threads-pipe 276115 +6.6e+15% 1.832e+19 TOTAL proc-vmstat.nr_tlb_remote_flush_received v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 497469 ~ 1% -97.8% 10855 grantley/micro/kbuild/200% 10025 ~ 0% +3.8e+15% 3.85e+17 lkp-a04/micro/netperf/120s-200%-TCP_CRR 9772 ~ 0% -51.4% 4752 lkp-a04/micro/netperf/120s-200%-TCP_MAERTS 9877 ~ 1% +1.7e+15% 1.692e+17 lkp-a04/micro/netperf/120s-200%-TCP_RR 9818 ~ 0% +1.7e+11% 1.679e+13 lkp-a04/micro/netperf/120s-200%-TCP_SENDFILE 9850 ~ 0% -40.6% 5848 lkp-a04/micro/netperf/120s-200%-UDP_RR 16816 ~ 1% +5.8e+14% 9.8e+16 lkp-snb01/micro/hackbench/1600%-threads-pipe 8659 ~ 1% +2071.0% 187996 lkp-snb01/micro/hackbench/1600%-threads-socket 572289 +1.1e+14% 6.522e+17 TOTAL proc-vmstat.nr_tlb_local_flush_all v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1.807e+08 ~ 1% +56.2% 2.822e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 1.807e+08 +56.2% 2.822e+08 TOTAL proc-vmstat.numa_local v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1.807e+08 ~ 1% +56.2% 2.822e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 1.807e+08 +56.2% 2.822e+08 TOTAL proc-vmstat.numa_hit v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1.818e+08 ~ 1% +56.0% 2.836e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 1.818e+08 +56.0% 2.836e+08 TOTAL proc-vmstat.pgfree v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 2228224 ~15% +41.2% 3145728 ~ 0% nhm8/micro/dbench/100% 2228224 +41.2% 3145728 TOTAL meminfo.DirectMap1G v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 8.696e+08 ~ 1% -33.0% 5.827e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 8.696e+08 -33.0% 5.827e+08 TOTAL interrupts.RES v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1.771e+08 ~ 1% +50.4% 2.664e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 1.771e+08 +50.4% 2.664e+08 TOTAL proc-vmstat.pgalloc_normal v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 4022784 ~ 8% -22.7% 3107840 ~ 0% nhm8/micro/dbench/100% 4022784 -22.7% 3107840 TOTAL meminfo.DirectMap2M v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 4821300 ~ 1% -14.4% 4128651 lkp-snb01/micro/hackbench/1600%-threads-pipe 4821300 -14.4% 4128651 TOTAL proc-vmstat.pgfault v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1413677 ~ 0% -31.9% 962827 lkp-snb01/micro/hackbench/1600%-threads-pipe 1413677 -31.9% 962827 TOTAL vmstat.system.in v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 2.386e+09 ~ 0% -27.2% 1.737e+09 lkp-snb01/micro/hackbench/1600%-threads-pipe 2.386e+09 -27.2% 1.737e+09 TOTAL time.voluntary_context_switches v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 5575434 ~ 0% -26.3% 4108849 lkp-snb01/micro/hackbench/1600%-threads-pipe 5575434 -26.3% 4108849 TOTAL vmstat.system.cs v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 9.359e+08 ~ 1% -25.2% 6.999e+08 lkp-snb01/micro/hackbench/1600%-threads-pipe 9.359e+08 -25.2% 6.999e+08 TOTAL time.involuntary_context_switches v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1229364 ~ 1% +32.5% 1629469 lkp-snb01/micro/hackbench/1600%-threads-pipe 1229364 +32.5% 1629469 TOTAL time.minor_page_faults v3.13-rc7 eb9bbbe145c10a3b28a249c4a --------------- ------------------------- 1638 ~ 1% +25.4% 2054 lkp-snb01/micro/hackbench/1600%-threads-pipe 1638 +25.4% 2054 TOTAL time.user_time Thanks, Fengguang