From main:
| Benchmark | Time | CPU | Iterations | items_per_second |
|---|---|---|---|---|
| AllocateDeallocate/size:4096/real_time/threads:1 | 40.6 ns | 40.5 ns | 17256246 | 24.6592M/s |
| AllocateDeallocate/size:4096/real_time/threads:2 | 37.1 ns | 74.3 ns | 18816032 | 26.9313M/s |
| AllocateDeallocate/size:4096/real_time/threads:4 | 68.5 ns | 274 ns | 10096888 | 14.5911M/s |
| AllocateDeallocate/size:4096/real_time/threads:8 | 85.2 ns | 682 ns | 8969680 | 11.733M/s |
| AllocateDeallocate/size:4096/real_time/threads:16 | 64.1 ns | 1022 ns | 10904176 | 15.5995M/s |
| AllocateDeallocate/size:4096/real_time/threads:32 | 57.1 ns | 1033 ns | 13711680 | 17.5085M/s |
| AllocateDeallocate/size:65536/real_time/threads:1 | 45.0 ns | 45.0 ns | 15550007 | 22.2443M/s |
| AllocateDeallocate/size:65536/real_time/threads:2 | 52.1 ns | 104 ns | 18439302 | 19.1794M/s |
| AllocateDeallocate/size:65536/real_time/threads:4 | 76.0 ns | 304 ns | 9022692 | 13.1598M/s |
| AllocateDeallocate/size:65536/real_time/threads:8 | 87.0 ns | 696 ns | 9883360 | 11.4977M/s |
| AllocateDeallocate/size:65536/real_time/threads:16 | 61.2 ns | 978 ns | 11521504 | 16.3496M/s |
| AllocateDeallocate/size:65536/real_time/threads:32 | 52.3 ns | 983 ns | 13423712 | 19.1278M/s |
| AllocateDeallocate/size:1048576/real_time/threads:1 | 46.2 ns | 46.2 ns | 15085182 | 21.6221M/s |
| AllocateDeallocate/size:1048576/real_time/threads:2 | 48.8 ns | 97.6 ns | 15959920 | 20.4852M/s |
| AllocateDeallocate/size:1048576/real_time/threads:4 | 72.6 ns | 290 ns | 8770500 | 13.7701M/s |
| AllocateDeallocate/size:1048576/real_time/threads:8 | 82.6 ns | 661 ns | 9626720 | 12.1014M/s |
| AllocateDeallocate/size:1048576/real_time/threads:16 | 60.6 ns | 970 ns | 11545920 | 16.489M/s |
| AllocateDeallocate/size:1048576/real_time/threads:32 | 55.2 ns | 976 ns | 13927584 | 18.1264M/s |
| AllocateDeallocate/size:16777216/real_time/threads:1 | 47.3 ns | 47.3 ns | 14798147 | 21.1493M/s |
| AllocateDeallocate/size:16777216/real_time/threads:2 | 53.0 ns | 106 ns | 12193390 | 18.8762M/s |
| AllocateDeallocate/size:16777216/real_time/threads:4 | 73.1 ns | 292 ns | 8888352 | 13.673M/s |
| AllocateDeallocate/size:16777216/real_time/threads:8 | 83.5 ns | 667 ns | 8606728 | 11.9754M/s |
| AllocateDeallocate/size:16777216/real_time/threads:16 | 61.3 ns | 978 ns | 11482768 | 16.3183M/s |
| AllocateDeallocate/size:16777216/real_time/threads:32 | 53.5 ns | 965 ns | 14079456 | 18.6938M/s |
After commenting out the body of UpdateAllocatedBytes:
| Benchmark | Time | CPU | Iterations | items_per_second |
|---|---|---|---|---|
| AllocateDeallocate/size:4096/real_time/threads:1 | 38.1 ns | 38.1 ns | 18245705 | 26.2773M/s |
| AllocateDeallocate/size:4096/real_time/threads:2 | 21.1 ns | 42.2 ns | 33524684 | 47.439M/s |
| AllocateDeallocate/size:4096/real_time/threads:4 | 11.2 ns | 44.6 ns | 64754672 | 89.6438M/s |
| AllocateDeallocate/size:4096/real_time/threads:8 | 6.32 ns | 50.5 ns | 80000000 | 158.29M/s |
| AllocateDeallocate/size:4096/real_time/threads:16 | 5.92 ns | 94.7 ns | 120264464 | 168.939M/s |
| AllocateDeallocate/size:4096/real_time/threads:32 | 5.29 ns | 93.8 ns | 157807072 | 189.189M/s |
| AllocateDeallocate/size:65536/real_time/threads:1 | 42.6 ns | 42.6 ns | 16384852 | 23.4741M/s |
| AllocateDeallocate/size:65536/real_time/threads:2 | 22.2 ns | 44.4 ns | 31642666 | 45.0489M/s |
| AllocateDeallocate/size:65536/real_time/threads:4 | 11.4 ns | 45.6 ns | 61972996 | 87.7315M/s |
| AllocateDeallocate/size:65536/real_time/threads:8 | 6.44 ns | 51.5 ns | 103990392 | 155.353M/s |
| AllocateDeallocate/size:65536/real_time/threads:16 | 6.15 ns | 98.2 ns | 112948512 | 162.575M/s |
| AllocateDeallocate/size:65536/real_time/threads:32 | 5.65 ns | 98.2 ns | 153753472 | 176.919M/s |
| AllocateDeallocate/size:1048576/real_time/threads:1 | 42.5 ns | 42.5 ns | 16411385 | 23.5441M/s |
| AllocateDeallocate/size:1048576/real_time/threads:2 | 22.2 ns | 44.4 ns | 31565932 | 45.0146M/s |
| AllocateDeallocate/size:1048576/real_time/threads:4 | 11.5 ns | 45.9 ns | 61519376 | 87.1179M/s |
| AllocateDeallocate/size:1048576/real_time/threads:8 | 6.44 ns | 51.5 ns | 100738824 | 155.244M/s |
| AllocateDeallocate/size:1048576/real_time/threads:16 | 6.20 ns | 99.2 ns | 114865280 | 161.251M/s |
| AllocateDeallocate/size:1048576/real_time/threads:32 | 5.52 ns | 97.8 ns | 139016768 | 181.033M/s |
| AllocateDeallocate/size:16777216/real_time/threads:1 | 43.4 ns | 43.4 ns | 16132988 | 23.0522M/s |
| AllocateDeallocate/size:16777216/real_time/threads:2 | 22.2 ns | 44.4 ns | 31198652 | 45.0013M/s |
| AllocateDeallocate/size:16777216/real_time/threads:4 | 14.4 ns | 57.7 ns | 56729008 | 69.2928M/s |
| AllocateDeallocate/size:16777216/real_time/threads:8 | 7.73 ns | 61.8 ns | 98822728 | 129.359M/s |
| AllocateDeallocate/size:16777216/real_time/threads:16 | 6.24 ns | 99.5 ns | 111817376 | 160.287M/s |
| AllocateDeallocate/size:16777216/real_time/threads:32 | 5.13 ns | 97.6 ns | 140379712 | 194.757M/s |
Just before a recent change in Arrow 13, https://github.com/apache/arrow/commit/ddfa8eed9b188fcc7b38767d1858c2588c588f05#diff-2111aac8ee579e238fb15d4380f2ea1e2f3e2830da939ec3f07c61dc68038d1f. The result is intermediate between the two extremes:
| Benchmark | Time | CPU | Iterations | items_per_second |
|---|---|---|---|---|
| AllocateDeallocate/size:4096/real_time/threads:1 | 39.8 ns | 39.8 ns | 17704095 | 25.1397M/s |
| AllocateDeallocate/size:4096/real_time/threads:2 | 33.0 ns | 66.0 ns | 21156262 | 30.2882M/s |
| AllocateDeallocate/size:4096/real_time/threads:4 | 49.3 ns | 197 ns | 14550456 | 20.2986M/s |
| AllocateDeallocate/size:4096/real_time/threads:8 | 53.1 ns | 425 ns | 13473320 | 18.8344M/s |
| AllocateDeallocate/size:4096/real_time/threads:16 | 29.1 ns | 462 ns | 23901536 | 34.4059M/s |
| AllocateDeallocate/size:4096/real_time/threads:32 | 26.5 ns | 463 ns | 31765728 | 37.7303M/s |
| AllocateDeallocate/size:65536/real_time/threads:1 | 44.0 ns | 44.0 ns | 15886376 | 22.7218M/s |
| AllocateDeallocate/size:65536/real_time/threads:2 | 35.6 ns | 71.3 ns | 17757214 | 28.0662M/s |
| AllocateDeallocate/size:65536/real_time/threads:4 | 38.0 ns | 152 ns | 19507004 | 26.2896M/s |
| AllocateDeallocate/size:65536/real_time/threads:8 | 36.9 ns | 295 ns | 19788320 | 27.098M/s |
| AllocateDeallocate/size:65536/real_time/threads:16 | 29.8 ns | 477 ns | 23458016 | 33.5527M/s |
| AllocateDeallocate/size:65536/real_time/threads:32 | 27.6 ns | 482 ns | 32773568 | 36.2807M/s |
| AllocateDeallocate/size:1048576/real_time/threads:1 | 45.3 ns | 45.3 ns | 15442833 | 22.0897M/s |
| AllocateDeallocate/size:1048576/real_time/threads:2 | 41.7 ns | 83.4 ns | 17880106 | 23.9737M/s |
| AllocateDeallocate/size:1048576/real_time/threads:4 | 32.6 ns | 131 ns | 18217508 | 30.6478M/s |
| AllocateDeallocate/size:1048576/real_time/threads:8 | 36.3 ns | 290 ns | 19272912 | 27.5667M/s |
| AllocateDeallocate/size:1048576/real_time/threads:16 | 30.1 ns | 481 ns | 23301200 | 33.2427M/s |
| AllocateDeallocate/size:1048576/real_time/threads:32 | 27.8 ns | 489 ns | 31171680 | 35.9621M/s |
| AllocateDeallocate/size:16777216/real_time/threads:1 | 45.6 ns | 45.6 ns | 15317019 | 21.9423M/s |
| AllocateDeallocate/size:16777216/real_time/threads:2 | 44.7 ns | 89.4 ns | 16540960 | 22.3799M/s |
| AllocateDeallocate/size:16777216/real_time/threads:4 | 37.8 ns | 151 ns | 19134904 | 26.4453M/s |
| AllocateDeallocate/size:16777216/real_time/threads:8 | 36.4 ns | 291 ns | 19363048 | 27.4389M/s |
| AllocateDeallocate/size:16777216/real_time/threads:16 | 30.0 ns | 479 ns | 23268240 | 33.3274M/s |
| AllocateDeallocate/size:16777216/real_time/threads:32 | 27.8 ns | 486 ns | 30116928 | 35.9979M/s |