Re: [PATCH V2 0/6][RFC] futex: FUTEX_LOCK with optional adaptive spinning

From: Ulrich Drepper
Date: Tue Apr 06 2010 - 10:48:15 EST

On Tue, Apr 6, 2010 at 01:48, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> Âtry
> Âspin
> Âtry
> Âsyscall

This is available for a long time in the mutex implementation
(PTHREAD_MUTEX_ADAPTIVE_NP mutex type). It hasn't show much
improvement if any. There were some people demanding this support for
as far as I know they are not using it now. This is adaptive
spinning, learning from previous calls how long to wait. But it's
still unguided. There is no way to get information like "the owner
has been descheduled".
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at