On 07/06/2010 01:19 PM, Pedro Ribeiro wrote: > Hi, > > I've been using -rt kernels since 2.6.29 because I do realtime audio > on my laptop. > > The audio stability has been steadily improving since, and now I find > that I can use 2.6.34 without the -rt patch and achieve the same > stability as 2.6.33-rt - well, my latency requirements aren't that > high, I just need to maintain 8.9ms completely stable, however before > .34 it would be impossible without the -rt patch. It's been possible to achieve low-latency for audio (using JACK) with the vanilla kernel for a while now. The -rt patch still has two major advantages: - it guarantees low latency. (pretty much a requirement for live-performance on stage) - it allows to assign scheduling priorities to IRQ handlers. (comes in handy for crappy machines that share the soundcard's IRQ) As for your questions: I don't know the details, hopefully someone else here can enlighten us. I'd be interested in that as well. > So out of curiosity, what changed for .34? According to [1], on .33 > Raw Spinlock Annotation was introduced in the mainline kernel. > However, as said above, I can't get the same performance than with > .34. > > I remember that I read somewhere that the one the biggest problems > with latency requirements was the use of the BKL. Do you think there > will be a significant improvement of latency (in specific cases of > course) with the scheduled removal of BKL for 2.6.36? > > Thanks for the help, > Pedro > > [1] http://www.osadl.org/Realtime-Linux.projects-realtime-linux.0.html -- Robin Gareus mail: robin@xxxxxxxxxx site: http://gareus.org/ chat: xmpp:rgareus@xxxxx blog: http://rg42.org/ lab : http://citu.fr/ Public Key at http://pgp.mit.edu/ Fingerprint : 7107 840B 4DC9 C948 076D 6359 7955 24F1 4F95 2B42 -- 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
