Re: [PATCH 06/12] hdaps: Limit hardware query rate

From: Pavel Machek
Date: Tue Aug 08 2006 - 08:49:26 EST


> The current hdaps driver queries the hardware on (almost) any sysfs read.
> Since fresh readouts are genereated by the hardware at a constant rate,
> this means apps are eating each other's events. Also, polling multiple
> attributes will genereate excessive hardware queries and excessive CPU
> load due to the duration of the hardware query transaction.
> With this patch, the driver will normally update its cached readouts
> only in its timer function (which exists anyway, for the input device).
> If that read failed, it will be retried upon the actual sysfs access.
> In all cases, query rate is bounded and apps will get reasonably
> fresh and usually cached readouts.
> The polling rate is increased to 50Hz, as needed by the hdaps daemon.
> A later patch makes this configurable.
> Signed-off-by: Shem Multinymous <multinymous@xxxxxxxxx>

I'd insert fewer blank lines, otherwise patch looks ok to me.

Signed-off-by: Pavel Machek <pavel@xxxxxxx>

Thanks for all the (sleeping) penguins.
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