On Fri, Aug 13, 2010 at 2:05 AM, Sven-Thorsten Dietrich <thebigcorporation@xxxxxxxxx> wrote: > On Thu, 2010-08-12 at 23:17 -0400, jordan johnston wrote: >> > Google did Android and even Palm woke up (just long enough to watch its own >> > demise). >> > >> > The rest is history. >> > >> > Except of course putting the RT Kernel in Android. >> >> As i understand it, many Android users are using the BFS patchset, and >> have been for a while. BFS pretty much does what "the end result of >> using the rt-patches" accomplish, minus rtirq, spin-locks, etc. You >> will get the desired >> responsiveness that using RT would give you. >> > > I assume that it might well depend to some extent on whether I am > pumping market data feeds into a processing model using 512 CPUs or > playing a game on my Nexus-1, but I won't disagree agree with you on the > importance of task-appropriate efficient scheduling, appropriate > workload partitioning, and all that jazz. agreed, 100%. the "case in point" here is i was commenting on android. When talking on the scale of 512 CPUs, RT is the choice hands down. i should have said "You will get the desired responsiveness that using RT would give you ON ANDROID". >> Im pretty sure that is why Zen-kernel has a git repository "very >> specifically" for android (BFS is the default kernel setting). I'm >> sure there are other goodies for android in there too. >> >> www.zen-kernel.org >> >> I don't know much about the Android repo's state (as it's fairly new). >> but worth a >> look for your "rt-usage" (ie. performance/responsiveness) for android. >> As i do not own an Android, i have not tested it, but i have talked >> with people who do.. >> >> I'm waiting to see what 2.6.35 holds for RT.... but personally i am >> using BFS and 2.6.34 with a lot of performance tuning (a good deal of >> time spent analyzing/tuning) and i am yielding better results not >> using the upstream rt-patches. >> we will see what happens in 2.6.35/36.... >> > > Sounds good. I know there has been some extensive discussion about the > interpretation and applicability of the various scheduler performance > metrics, including special examination of BFS vs. CFS - and I definitely > think that has been hashed out in gore and detail already. > > But if you have some pretty plots that characterize performance for your > platform, vs. Preempt-RT, I am always interested in looking at pictures > and numbers about what's happening on the other side of the fence. Of course, i wasn't interested in getting into the CFS/BFS war. they are both valid and useful. I also think the existence of both, is a good thing. if anything it's healthy for development. I do plan to document some of my testing/usage but not until i get my new 3u rack up and running. jordan -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
