On Mon, 3 Aug 2009, Paul Neaveill wrote:

> Sorry if someone responded and we missed it, but despite much googling and all of that, am still working on getting my own kernel(s) [2 machines] going with the following as had been suggested last week:
>
> preempt_RCU
> No_Hz
> HZ_1000
>
> and the other Rock-solid low-latency audio tweaks
> 99 ff migration
> 99 ff posixcputmr
> 98 ff IRQ-8 (real-time clock)
> 97 ff audio IRQ
> 80 rr Jack
>
> Found the preempt_RCU and HZ_1000 spots in the debian/ubuntu kernel hack, still looking for the rest please.?
>
> ** Would really appreciate the assistance with figuring out where/how to put those.

I never did get an answer to some of those questions either, so I figured maybe I'd been asking too many. (I have been posting a lot of them lately.)

I think the ones you've got at the top for kernel options should be safe. I'm going to try -- at least initially -- not adjusting any IRQ priorities though. It might work, considering I've got a fast machine, and from what I hear, there are even people getting away with ordinary non-RT kernels these days.

Preempt RCU was supposed to be buggy for awhile, but tested now for two years... (Source: LKML)

Somebody said NO_HZ was actually a good thing on a laptop being used for pro-audio, and I suppose if you can do well on a laptop you can do well anywhere... (Source: Some guy with a laptop.)

And HZ_1000 is recommended almost everywhere.

I don't know what the meaning of NO_HZ and HZ_1000 is together, but I guess it'd mean a jiffy rate of 1000Hz, but only when interrupts are needed?

I'm just putting stuff together from lots of googling too...

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