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Re: weighted-fair queuing

Cross-posted to 2 groups.

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"Mark" <mark_cruzNOTFORSPAM@hotmail.com> writes:

[...]

> Weights that can be assigned by user from upper layer software are in range 
> 1-32, the max weight value in h/w is 131072, therefore I need some way to 
> scale down input value (1-32) to properly fit in the hardware.

This looks rather as if you would need to scale it up. Given that you
need to map a value in the range (1, 2^5) [2^5 ::= 2 to the fifth
power] to the range (0, 2^17), an obvious idea would be

static inline unsigned map_weight(unsigned weight)
{
	return weight * (1 << 12);
}

(since 2^17/2^5 = 2^12, 131072 / 32 = 4096).

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Thread

weighted-fair queuing "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2011-10-20 19:19 -0400
  Re: weighted-fair queuing Rainer Weikusat <rweikusat@mssgmbh.com> - 2011-10-21 00:51 +0100
    Re: weighted-fair queuing Rainer Weikusat <rweikusat@mssgmbh.com> - 2011-10-21 02:42 +0100
      Re: weighted-fair queuing "Mark" <mark_cruzNOTFORSPAM@hotmail.com> - 2011-10-21 21:28 -0400

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