Subject: Re: RT patch acceptance
From: Thomas Gleixner <tglx@linutronix.de>
Reply-To: tglx@linutronix.de
To: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@muc.de>, Takashi Iwai <tiwai@suse.de>,
       Sven-Thorsten Dietrich <sdietrich@mvista.com>, dwalker@mvista.com,
       bhuey@lnxw.com, nickpiggin@yahoo.com.au, hch@infradead.org,
       akpm@osdl.org, linux-kernel@vger.kernel.org
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Organization: linutronix
Date: Mon, 30 May 2005 13:15:41 +0200
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On Mon, 2005-05-30 at 12:33 +0200, Ingo Molnar wrote:

> FYI, to get good latencies for jack you currently need the -RT tree and 
> CONFIG_PREEMPT. (see Lee Revell's and Rui Nuno Capela's extensive tests)
> 
> In other words, cond_resched() in might_sleep() (PREEMPT_VOLUNTARY, 
> which i announced Jul 9 last year) is _not_ good enough for 
> advanced-audio (jack) users. PREEMPT_VOLUNTARY is mostly good enough for 
> simple audio playback / gaming.

It's neither good enough for a lot of embedded applications, but _RT is.

tglx


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