Con, I've tried running Volanomark and found a 80% regression with RSDL 0.31 scheduler on 2.6.21-rc4 on a 2 socket Core 2 quad cpu system (4 cpus per socket, 8 cpus for system).
The results are sensitive to rr_interval. Using Con's patch to increase rr_interval to a large value of 100, the regression reduced to 30% instead of 80%. I ran Volanomark in loopback mode with 10 chatrooms (20 clients per chatroom) configuration, with each client sending out 10000 messages. http://www.volano.com/benchmarks.html There are significant differences in the vmstat runqueue profile between the 2.6.21-rc4 and the one with RSDL. There are a lot less runnable jobs (see col 2) with RSDL 0.31 (rr_interval=15) and higher idle time. 2.6.21-rc4 (original) Time procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- (sec) r b swpd free buff cache si so bi bo in cs us sy id wa st 10 2 3 0 2642376 15320 194612 0 0 161 875 44 70 1 1 92 5 0 20 379 0 0 1573484 15680 195152 0 0 46 237 350 152686 9 8 81 2 0 30 395 0 0 1579056 15704 195152 0 0 0 30 284 1017337 44 48 8 0 0 40 469 0 0 1586368 15744 195144 0 0 0 50 284 1075456 42 51 7 0 0 50 425 0 0 1593628 15756 195156 0 0 0 40 289 1108785 41 52 6 0 0 60 394 0 0 1599452 15772 195156 0 0 0 31 284 1160316 41 53 5 0 0 70 65 0 0 1599684 15788 195160 0 0 0 20 284 1075719 40 52 8 0 0 80 424 0 0 1599320 15928 195168 0 0 1 122 314 1187583 41 54 4 0 0 90 438 0 0 1600188 15944 195164 0 0 0 41 289 1171807 40 53 6 0 0 100 412 0 0 1599312 15968 195160 0 0 0 22 284 1183832 41 54 5 0 0 110 398 0 0 1599716 15976 195176 0 0 0 6 283 1227036 42 55 3 0 0 120 382 0 0 1599468 15992 195180 0 0 0 23 286 1160802 40 54 6 0 0 130 370 0 0 1599912 16008 195180 0 0 0 10 284 1159618 42 52 7 0 0 2.6.21-rc4 with RSDL 0.31 Time procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- (sec) r b swpd free buff cache si so bi bo in cs us sy id wa st 10 2 3 0 2644892 15316 194612 0 0 160 869 44 64 1 1 92 5 0 20 2 0 0 1577512 15388 194984 0 0 24 93 293 3935 3 2 95 1 0 30 2 0 0 1583888 15412 194984 0 0 0 33 284 638668 28 39 33 0 0 40 2 0 0 1591208 15444 194972 0 0 0 50 284 307181 19 28 53 0 0 50 4 0 0 1598364 15460 194980 0 0 0 39 285 311971 18 29 53 0 0 60 8 0 0 1604108 15476 194980 0 0 0 29 284 308109 18 29 53 0 0 70 9 0 0 1603792 15492 194992 0 0 0 8 283 315947 18 29 52 0 0 80 11 0 0 1602440 15784 195032 0 0 20 161 342 310849 18 29 52 1 0 90 1 0 0 1602504 15792 195160 0 0 0 37 287 317667 18 29 53 0 0 100 1 0 0 1603140 15824 195144 0 0 0 25 284 319106 18 30 52 0 0 110 7 0 0 1602760 15832 195160 0 0 0 6 283 316589 17 29 53 0 0 120 12 0 0 1602644 15848 195164 0 0 0 22 285 320019 17 30 52 0 0 130 1 0 0 1602644 15864 195164 0 0 0 10 283 319537 17 30 53 0 0 140 6 0 0 1601744 16016 195176 0 0 2 104 312 316836 18 30 52 0 0 2.6.21-rc4 with RSDL 0.31, rr_interval = 100 Time procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- (sec) r b swpd free buff cache si so bi bo in cs us sy id wa st 10 4 2 0 2679976 16696 195380 0 0 65 353 40 33 0 1 97 2 0 20 296 0 0 1602676 16780 195764 0 0 22 104 294 151873 8 9 82 1 0 30 298 0 0 1601280 16808 195756 0 0 0 14 284 1164355 41 56 3 0 0 40 272 0 0 1600108 16832 195764 0 0 0 12 284 1205454 42 57 1 0 0 50 321 0 0 1599128 16848 195760 0 0 0 25 287 1209822 41 58 1 0 0 60 281 0 0 1598764 16864 195760 0 0 0 12 283 1206452 41 57 2 0 0 70 287 0 0 1598888 16880 195764 0 0 0 15 284 1206103 40 58 2 0 0 80 276 0 0 1597764 16904 195776 0 0 0 33 285 1193156 39 58 3 0 0 90 293 0 0 1598144 16920 195780 0 0 0 14 284 1215350 39 59 2 0 0 100 287 0 0 1598260 16936 195780 0 0 0 11 283 1236433 40 58 2 0 0 110 257 0 0 1597872 16952 195784 0 0 0 10 283 1234983 40 59 1 0 0 120 255 0 0 1598640 16968 195784 0 0 0 16 284 1178551 39 58 3 0 0 130 200 0 0 1598764 16984 195788 0 0 0 13 284 1223963 39 59 2 0 0 140 274 0 0 1598632 17008 195792 0 0 0 22 284 1179931 40 57 3 0 0 150 278 0 0 1598616 17024 195792 0 0 0 21 286 1215157 39 59 2 0 0 - Tim - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/