On Sat, 28 Jun 2003 15:16, Con Kolivas wrote:
> For my sins I've included what I thought was necessary for this patch.
>
> The interactivity for tasks is based on the sleep avg accumulated divided
> by the running time of the task. However since the accumulated time is not
> linear with time it now works on the premise that running time is an
> exponential function entirely. Pat Erley was the genius who implemented
> this simple exponential function in surprisingly low overhead integer
> maths.
>
> Also added was some jiffy wrap logic (as if anyone would still be running
> my patch in 50 days :P).
>
> Long sleepers were reclassified as idle according to the new exponential
> logic.
>
> If you test, please note this works better at 1000Hz.
>
> Attached also is my bastardised version of Ingo's timeslice granularity
> patch. This round robins tasks on the active array every 10ms, which
> _might_ be detrimental in throughput applications but has not been
> benchmarked. However for desktops it does wonders to smoothing out the
> jerkiness of X and I highly recommend using this in combination with the
> O1int patch.
>
> This is very close to all the logic I wanted to implement. It might need
> more tuning... Note parent penalty, child penalty and exit weight
> (uppercase) no longer do anything.
>
> Please test and comment.
>
> Con
>
> P.S. In the words of Zwane - there is always a corner case. Corner case I
> think I still need to tackle is the application that spins madly waiting
> for it's child to start, and in the process it is the parent that is
> starving the child by being higher priority than it. This seems to be a
> coding style anomaly brought out by the scheduler.

And just for good measure here is the latest with a slight addition that helps 
X smoothness over time. It gives the sleep_avg a little headroom so it 
doesn't drop from interactive as easily with bursts of cpu activity.

Con