On Wed, 21 May 2008, Mike Galbraith wrote: > On Tue, 2008-05-20 at 00:46 -0400, Steven Rostedt wrote: > > We are pleased to announce the 2.6.24.7-rt8 tree, which can be > > downloaded from the location: > > > > http://rt.et.redhat.com/download/ > > I ran mysql+oltp (ro) on 2.6.24.7-rt7 and 2.6.25-rt2 to compare > throughput to their parent trees, and ended up with strange (and > verified) looking performance curves for both trees. The changes in > 2.6.24.7-rt8 and 2.6.25.4-rt3 cured the primary oddities. The difference between 24-rt7 and 24-rt8 as well as with 25-rt2 and 25-rt3 is the deserialization of rwlocks. The rt patch as always serialized readers to allow for priority inheritance with rwlocks. I wrote a patch to break that and allow for multiple readers and still keep the priority inheritance. Your test probably had a bottle neck on a rwlock (same for rwsems) somewhere that the new code solved. -- Steve -- 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
