Re: [PATCH 2/2] UBIFS: start using hrtimers

From: Peter Zijlstra
Date: Fri May 29 2009 - 09:32:48 EST

On Fri, 2009-05-29 at 18:09 +0300, Artem Bityutskiy wrote:
> From: Artem Bityutskiy <Artem.Bityutskiy@xxxxxxxxx>
> Subject: [PATCH 2/2] UBIFS: start using hrtimers
> UBIFS uses timers for write-buffer write-back. It is not
> crucial for us to write-back exactly on time. We are fine
> to write-back a little earlier or later. And this means
> we may optimize UBIFS timer so that it could be groped
> with a close timer event, so that the CPU would not be
> waken up just to do the write back. This is optimization
> to lessen power consumption, which is important in
> embedded devices UBIFS is used for.
> hrtimers have a nice feature: they are effectively range
> timers, and we may defind the soft and hard limits for
> it. Standard timers do not have these feature. They may
> only be made deferrable, but this means there is effectively
> no hard limit. So, we will better use hrtimers.
> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@xxxxxxxxx>
> ---

Seems sane enough from a hrtimer POV, but isn't this already
functionality that the VFS/pdflush provide?

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