From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] codel: use Newton method instead of sqrt()
 and divides
Date: Sat, 12 May 2012 16:45:13 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 12 May 2012 22:40:56 +0200

> 24 bit of precision for the reciprocal value is more than enough (Van
> suggested 16 bits in fact), so we have actually room for 7 bits if
> needed.

Using a u16 would also work for me.

> By the way, gcc on x86 generates nice "and 0xfffffffe,%eax" instruction
> for (vars->rec_inv_sqrt << 1).

Yeah but what do stores of ->rec_inv_sqrt look like?