Messages in this thread | | | Subject | Re: 2.6.16-rt1 | From | Steven Rostedt <> | Date | Wed, 22 Mar 2006 22:13:53 -0500 |
| |
On Wed, 2006-03-22 at 10:10 -0600, K.R. Foley wrote: > K.R. Foley wrote: > > Ingo Molnar wrote: > >> * K.R. Foley <kr@cybsft.com> wrote: > >> > >>> Sorry I have been onsite and completely buried today. Am running an > >>> initial test on both UP and SMP now with 2.6.16-rt1. UP doesn't look > >>> bad at all. SMP on the other hand doesn't look so good. I will give > >>> -rt4 a spin when these are done. > >> thanks for the testing - i'll check SMP too. > >> > >> Ingo > >> > > OK. On my dual 933 under heavy load I get the following with 2.6.16-rt4 > > and I get tons of missed interrupts. Running 2.6.15-rc16 I get a max of > > 88usec with most falling under 30usec. On my UP AthlonXP 1700 I get a > > max of 19usec with 2.6.16-rt4 under load. What sort of results do you > > see on SMP? > > > > Found something interesting. Having Wakeup latency timing turned on > makes a HUGE difference. I turned it off and recompiled and now I am > seeing numbers back in line with what I expected from 2.6.16-rt4. Sorry, > but I had no idea it would make that much difference. I don't have a > complete run yet, but I have seen enough to know that I am not seeing > tons of missed interrupts and the highest reported latency thus far is > 61 usec.
Hmm, high wake up latency on SMP and not on UP...
Ingo, could this be due to the migrate task latency? This was where I saw the problem with the 50ms latency running hack bench. I remember there was a bug in the older latency tool that didn't catch this latency before.
I'm just getting back to looking at the latest stuff. I had some customer deliveries lately and haven't had time to look at the new goodies.
-- Steve
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |