On Thu, Sep 08, 2005 at 08:38:02PM -0500, Reuben Martin wrote: > On 9/7/05, guy <sayhi2guy@xxxxxxxxxxxxx> wrote: > > Hi > > I'm just about to compile a 2.6.13 kernel for low latency audio work. > > The docs I have accessed are either confusing (sorry if its just me ;0) > > ) or rendered out of date by kernel developments. > > I know that some features such as pre-empt are now in the kernel. Which > > patches (if any) would you folks advise that I should apply. I am also > > unsure if should enable the 'big kernel lock' feature. > > Thanks in advance for any help > realtime-preempt patches are the latest and greatest for latency > improvements. They are very actively maintained by Ingo Molnar, same > guy who created the preempt patches for the 2.4 kernel series. For historical clarification ( and someone correct me if I'm wrong on any of this ), Ingo did a set of low latency patches for 2.2/2.4 that basically showed that breaking up long code pathes could improve linux's latency performance. These were proof of concept patches, in a sense, but not accepted, nor intended, for the mainline kernel. Andrew Morton created a smaller and more tightly focused set of long-code-path-splitting low-latency patches for 2.4 inspired by Ingo's earlier work. These were intended to find an approach to achieving low-latency more acceptable to the kernel devs. Robert Love created a set of Preemption patches for 2.4 that were commonly applied along with Andrew's LL patches. The preemption patches were a different approach to achieve low-latency which allowed code paths which might run for a long time to be marked as pre-emptible. Much of Andrew and Robert's work on 2.4 was incorporated into the 2.5 development kernel and thus the 2.6 series. However there were still latency problems with 2.6, so Ingo has again taken the lead in producing the current series of realtime-preemption patches. A lot of this work is now present in the mainline 2.6.13.x kernel. > http://people.redhat.com/mingo/realtime-preempt/ > > This patch removes "big kernel lock" option. (You don't want it and > the patch at the same time) > > The patch is updated every couple of days. > > Good luck. > -Reuben -- Eric Dantan Rzewnicki | Systems Administrator Technical Operations Division | Radio Free Asia 2025 M Street, NW | Washington, DC 20036 | 202-530-4900 CONFIDENTIAL COMMUNICATION This e-mail message is intended only for the use of the addressee and may contain information that is privileged and confidential. Any unauthorized dissemination, distribution, or copying is strictly prohibited. If you receive this transmission in error, please contact network@xxxxxxxx
