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Benchmark numbers based on: mv167-25Mhz, 5.1 Cache Cache Key Measurements Enabled Disabled Raw Context Switch Time 4 us 14 us Cyclic Test Time 172 us 638 us Suspend/Switch/Resume/Switch 23 us 86 us Kernel Timings Task Related taskSpawn 124 us 370 us taskInit 58 us 181 us taskActivate 12 us 33 us taskDelete 101 us 303 us Task Create / Delete 249 us 684 us taskLock CASE 1: no lock 3 us 4 us CASE 2: lock exists 2 us 5 us taskUnlock CASE 1: no lock 2 us 12 us CASE 2: lock exists 5 us 6 us taskSuspend CASE 1: ready task 11 us 30 us CASE 2: pended task 9 us 19 us CASE 3: suspended task 8 us 19 us CASE 4: delayed task 9 us 19 us taskResume CASE 1: ready task 6 us 19 us CASE 2: pended task 10 us 19 us CASE 3: suspended task 13 us 30 us CASE 4: delayed task 9 us 18 us Semaphore Related semBCreate 66 us 152 us semCCreate 46 us 150 us semMCreate 45 us 139 us semDelete Binary 49 us 157 us Counting 49 us 163 us Mutual Exclusion 48 us 157 us semGive CASE 1: tasks in queue Binary 18 us 44 us Counting 20 us 46 us Mutual Exclusion 25 us 59 us CASE 2: no tasks in queue Binary 4 us 8 us Counting 5 us 11 us Mutual Exclusion 6 us 15 us semTake CASE 1: semaphore available Binary 4 us 9 us Counting 5 us 11 us Mutual Exclusion 5 us 13 us CASE 2: semaphore unavailable Binary 10 us 25 us Counting 11 us 27 us Mutual Exclusion 4 us 12 us Semaphore Give / Take Binary 7 us 15 us Counting 9 us 21 us Mutual Exclusion 10 us 26 us semFlush Binary 11 us 20 us Counting 11 us 20 us Mutual Exclusion 10 us 16 us Miscellaneous Operating System Timings Message Queue Related msgQCreate 93 us 280 us msgQDelete 71 us 229 us msgQSend CASE 1: task pending 39 us 102 us CASE 2: no tasks pending 23 us 64 us CASE 3: queue full 14 us 45 us msgQReceive CASE 1: message available 20 us 62 us CASE 2: message unavailable 15 us 41 us Memory Related malloc 28 us 81 us free 32 us 104 us Watchdog Related wdCreate 42 us 106 us wdDelete CASE 1: timer started 48 us 160 us CASE 2: timer not started 44 us 150 us wdStart CASE 1: timer in queue 20 us 70 us CASE 2: no timer in queue 18 us 55 us wdCancel 11 us 34 us Floating-Point robot application 18 sec 51 sec [ editorial: If you care enough to count pico-seconds in comparing realtime kernels, you might want to actually get each of the evaluation copies from various vendors and test them yourself. But remember benchmarks are misleading and almost always biased and inaccurate. Given similar benchmark numbers, give or take a few microseconds, etc., your dollars are better spent in getting something you'll enjoy using. ] ----------------------------- According to WRS, using VxWorks 5.1 on mv167-25mhz (i82596 ethernet) w/ cache w/o cache enabled TCP/IP Throughput (KB/sec) 859 KB/sec 682 KB/sec No numbers available on latency. Using a reasonably fast processor 25Mhz MC68040 and a reasonably well made ethernet chip like SONIC or LANCE put together on a reasonable board design will achieve TCP throughput close to full bandwidth of ethernet. [ editorial: This, of course, is rather slow in comparison with other fast implementations, since a 16Mhz MC68020 with onboard LANCE or a PeeCee with an ethernet board can easily do the same. I know at least one implementation based on el-cheapo i486-50mhz/EISA/SONIC that does: 1170KB/sec. ]