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Date: Wed, 19 Nov 2014 07:16:37 +0100
From: Jan Bramkamp <crest@rlwinm.de>
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Subject: Re: FreeBSD max pipe size?
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On 14.10.2014 00:13, Michael Sierchio wrote:
> On Mon, Oct 13, 2014 at 2:46 PM, Jack Barber <jack@nyi.net> wrote:
> 
>> I am trying to set up dummynet with FreeBSD 9.3 and a 10 GB Fibre over
>> ethernet NIC (ix drivers).
>>
>> Dummynet appears to have a limit of 1.25 gigabits a second, and when I
>> start setting extremely large pipe values I start running into:

IIRC dummynet stores the pipe bandwidth in bits per seconds in a 32 bit
integer. This limits dummynet to ca. 4.2Gb/s. I don't know if this
representation is exported as part of a KBI. If it is changing it to a
64 bit integer would break the KBI and will probably require someone to
push for the change in 11-CURRENT and a set of compatible APIs for
10-STABLE and maybe even 9-STABLE.