[Xenomai-core] RTAI and Xenomai latency in kernel mode on AT91SAM9261-EK
Here, they are the last latency we get on AT91SAM9261-EK. As just now I haven't the board at home, I send the last result we stored. The prority of dbgu should be set to 6 instead of 7, but I can't assure it, for Xenomai. first Xenomai: #insmod /lib/modules/2.6.20.13/kernel/drivers/xenomai/testing/xeno_timerbench.ko #cd /usr/xenomai/bin/ #./latency -t 2 -p 150 -h -H 500 ---|--param|range-|--samples HSD|min| 3 - 4 |6 HSD|min| 4 - 5 | 12 HSD|min| 5 - 6 |5 HSD|min| 6 - 7 | 128 HSD|min| 7 - 8 | 405 HSD|min| 8 - 9 | 18 ---|--param|range-|--samples HSD|avg| 3 - 4 |6 HSD|avg| 4 - 5 | 12 HSD|avg| 5 - 6 |5 HSD|avg| 6 - 7 | 1248 HSD|avg| 7 - 8 | 1159824 HSD|avg| 8 - 9 | 1188725 HSD|avg| 9 - 10 | 238045 HSD|avg| 10 - 11 |78398 HSD|avg| 11 - 12 | 134973 HSD|avg| 12 - 13 | 132552 HSD|avg| 13 - 14 | 129661 HSD|avg| 14 - 15 | 137458 HSD|avg| 15 - 16 |49208 HSD|avg| 16 - 17 | 4532 HSD|avg| 17 - 18 | 2793 HSD|avg| 18 - 19 | 2494 HSD|avg| 19 - 20 | 2489 HSD|avg| 20 - 21 | 2373 HSD|avg| 21 - 22 | 3677 HSD|avg| 22 - 23 |15370 HSD|avg| 23 - 24 | 173411 HSD|avg| 24 - 25 | 181883 HSD|avg| 25 - 26 | 1509 HSD|avg| 26 - 27 | 5058 HSD|avg| 27 - 28 | 9483 HSD|avg| 28 - 29 |19691 HSD|avg| 29 - 30 |18397 HSD|avg| 30 - 31 |24228 HSD|avg| 31 - 32 |19539 HSD|avg| 32 - 33 |20438 HSD|avg| 33 - 34 |17420 HSD|avg| 34 - 35 |19943 HSD|avg| 35 - 36 |15057 HSD|avg| 36 - 37 |12100 HSD|avg| 37 - 38 | 1873 HSD|avg| 38 - 39 | 417 HSD|avg| 39 - 40 | 347 HSD|avg| 40 - 41 | 282 HSD|avg| 41 - 42 | 177 HSD|avg| 42 - 43 | 106 HSD|avg| 43 - 44 | 108 HSD|avg| 44 - 45 | 94 HSD|avg| 45 - 46 | 138 HSD|avg| 46 - 47 | 114 HSD|avg| 47 - 48 | 109 HSD|avg| 48 - 49 | 50 HSD|avg| 49 - 50 | 35 HSD|avg| 50 - 51 | 40 HSD|avg| 51 - 52 | 32 HSD|avg| 52 - 53 | 23 HSD|avg| 53 - 54 | 21 HSD|avg| 54 - 55 | 13 HSD|avg| 55 - 56 | 12 HSD|avg| 56 - 57 | 13 HSD|avg| 57 - 58 | 15 HSD|avg| 58 - 59 | 24 HSD|avg| 59 - 60 | 13 HSD|avg| 60 - 61 | 22 HSD|avg| 61 - 62 | 29 HSD|avg| 62 - 63 | 13 HSD|avg| 63 - 64 |7 HSD|avg| 64 - 65 |8 HSD|avg| 65 - 66 | 13 HSD|avg| 66 - 67 |8 HSD|avg| 67 - 68 |7 HSD|avg| 68 - 69 |5 HSD|avg| 69 - 70 |8 HSD|avg| 70 - 71 |4 HSD|avg| 71 - 72 |9 HSD|avg| 72 - 73 |8 HSD|avg| 73 - 74 | 13 HSD|avg| 74 - 75 |9 HSD|avg| 75 - 76 |6 HSD|avg| 76 - 77 |4 HSD|avg| 77 - 78 |5 HSD|avg| 78 - 79 | 11 HSD|avg| 79 - 80 |1 HSD|avg| 80 - 81 |2 HSD|avg| 81 - 82 |1 HSD|avg| 82 - 83 |4 HSD|avg| 83 - 84 |4 HSD|avg| 84 - 85 |6 HSD|avg| 85 - 86 |5 HSD|avg| 86 - 87 |1 HSD|avg| 87 - 88 |3 HSD|avg| 88 - 89 |2 HSD|avg| 89 - 90 |2 HSD|avg| 90 - 91 |1 HSD|avg| 92 - 93 |2 HSD|avg| 93 - 94 |1 HSD|avg| 94 - 95 |1 HSD|avg| 95 - 96 |1 HSD|avg| 96 - 97 |1 HSD|avg| 99 -100 |1 HSD|avg| 110 -111 |1 ---|--param|range-|--samples HSD|max| 25 - 26 |2 HSD|max| 26 - 27 |1 HSD|max| 27 - 28 |1 HSD|max| 29 - 30 |4 HSD|max| 30 - 31 |4 HSD|max| 31 - 32 |7 HSD|max| 32 - 33 | 18 HSD|max| 33 - 34 | 18 HSD|max| 34 - 35 | 36 HSD|max| 35 - 36 | 59 HSD|max| 36 - 37 | 72 HSD|max| 37 - 38 | 42 HSD|max| 38 - 39 | 40 HSD|max| 39 - 40 | 20 HSD|max| 40 - 41 | 26 HSD|max| 41 - 42 | 27 HSD|max| 42 - 43 | 25 HSD|max| 43 - 44 | 18 HSD|max| 44 - 45 | 16 HSD|max| 45 - 46 |8 HSD|max| 46 - 47 |3 HSD|max| 47 - 48 |3 HSD|max| 48 - 49 |8 HSD|max| 49 - 50 |2 HSD|max| 50 - 51 |5 HSD|max| 51 - 52 |4 HSD|max| 52 - 53 |3 HSD|max| 53 - 54 |2 HSD|max| 54 - 55 |2 HSD|max| 55 - 56 |2 HSD|max| 56 - 57 |3 HSD|max| 57 - 58 |4 HSD|max| 58 - 59 |7 HSD|max| 59 - 60 |4 HSD|max| 60 - 61 |1 HSD|max| 61 - 62 |4 HSD|
Re: [Xenomai-core] RTAI and Xenomai latency in kernel mode on AT91SAM9261-EK
Gregory CLEMENT wrote: Here, they are the last latency we get on AT91SAM9261-EK. As just now I haven't the board at home, I send the last result we stored. The prority of dbgu should be set to 6 instead of 7, but I can't assure it, for Xenomai. Hmm, hardware interrupt priorities must not impact the worst-case latency if I-pipe acks and mask them appropriately (the worst case is when multiple interrupts happen in a row, not at the same time). But this statement is not based on knowledge about potential pitfalls of this arch. Are there specialities that require this tweaking? first Xenomai: #insmod /lib/modules/2.6.20.13/kernel/drivers/xenomai/testing/xeno_timerbench.ko #cd /usr/xenomai/bin/ Which versions were you using for both tests? Do you still have the involved .configs? #./latency -t 2 -p 150 -h -H 500 ... ---|||||- RTS| 3.480| 11.779| 99.163| 0|14:23:01/14:23:01 It was run under calibrator load during more than 14 hours. Now RTAI: Oneshot timer with 500µs period, LATENCY =6000ns and SETUPTIME 1500 duration : 17h 1970/01/1 22:34:51 RTH|lat min|ovl min|lat avg|lat max|ovl max| overruns RTD| 3221| 2577| 4997| 26095| 53801| 0 RTD| 3221| 2577| 5163| 25451| 53801| 0 RTD| 3221| 2577| 5159| 25128| 53801| 0 RTD| 3221| 2577| 4799| 23518| 53801| 0 RTD| 3221| 2577| 4828| 25128| 53801| 0 RTD| 3221| 2577| 5089| 23518| 53801| 0 RTD| 3221| 2577| 4580| 23840| 53801| 0 RTD| 3221| 2577| 4924| 25128| 53801| 0 RTD| 3221| 2577| 4740| 24806| 53801| 0 RTD| 3221| 2577| 4251| 25128| 53801| 0 Again, what would simplify the discussion enormously is a function back-trace of the measured maximum latencies, just like latency -f generates. The numbers will become worse, for sure, but we would gain a very good overview about what is executed and what delayed which kernel. If you see a chance to perform such a test and you need some hints on the tracer setup (or did you use it before?), please let us know! Jan -- Siemens AG, Corporate Technology, CT SE 2 Corporate Competence Center Embedded Linux ___ Xenomai-core mailing list Xenomai-core@gna.org https://mail.gna.org/listinfo/xenomai-core
