On Sun, 2011-07-24 at 18:59 +0200, Robin Gareus wrote: > Hi Ralf, > > On Jul 24, 2011, at 4:12 AM, Ralf Mardorf wrote: > > > 3.0-rt2 > > > > So, the "rt patch emulation" ex kernel 2.6.39 might be less good than a > > kernel that is patched? > > It's not "emulation". A big part of the RT patch (e.g. threaded IRQ handlers) > was been merged into 2.6.39. > The goal of the Preempt-RT patch is to eventually end up completely in the > vanilla (aka mainline) kernel. > > http://lwn.net/Articles/440064/ is a nice read on the current state of it. > > > Until now I build > > > > linux-image-2.6.33.9-rt31_2.6.33.9-rt31-10.00.Custom_amd64.deb > > linux-image-2.6.39.1_2.6.39.1-10.00.Custom_amd64.deb > > > > but I only produced music with 2.6.33.9-rt31 until now, dunno if 2.6.39 > > isn't as good as a kernel-rt. > > > > Any information, experiences? > > I've been running 2.6.39 ever since it came out and used it for production. I > can't tell a difference between it and the rt-patched 2.6.33 for general > audio/video production. Neither will produce x-runs - unless I do sth stupid > or overload the system. > > Threaded IRQ handling of the audio-interface and [high priority] FIFO > scheduling are the important parts for low-latency audio and they're mainline > in 2.6.39 (FIFO scheduling was for a long time already). > > There's a lot of small (but complex) things the RT patch does that are not in > mainline yet (e.g pre-emptible memory-management, sleeping spinlocks) and can > improve the guaranteed response-time of dedicated [audio] processes. However > the gain [of code available in RT vs what is already mainline] is rather > small when compared to latency requirements of audio (us vs. ms) and thus can > be neglected on most systems. It'll probably give you an edge though. > > Long story short: If you just want to make music: stick with 2.6.39 or 3.0 - > If you have the time and ability to debug: give 3.0-rt3 a go. > > Even though the impact of the RT-preemt patch on pro-audio is becoming less > dramatic. It's a great project and important project. > > 2c, > robin
Thank you for the explanation Robin :). Cheers! Ralf -- Ubuntu-Studio-devel mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-devel
