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From: Garrett Cooper <yanegomi@gmail.com>
Subject: Re: polling's future [was: Re: Dynamic Ticks/HZ]
Date: Tue, 6 Nov 2012 07:38:07 -0800
To: Chuck Burns <break19@gmail.com>
Cc: "freebsd-current@freebsd.org" <freebsd-current@freebsd.org>
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On Nov 6, 2012, at 4:31 AM, Chuck Burns <break19@gmail.com> wrote:

> On Tuesday, November 06, 2012 12:36:46 PM Andre Oppermann wrote:
>> On 06.11.2012 12:30, Luigi Rizzo wrote:
>>> On Tue, Nov 06, 2012 at 11:23:34AM +0100, Andre Oppermann
> wrote:
>>> ...
>>>=20
>>>> Hi Luigi,
>>>>=20
>>>> do you agree on polling having outlived its usefulness in the light
>>>> of interrupt moderating NIC's and SMP
> complications/disadvantages?
>>>=20
>>> yes, we should let it rest in peace.
>>=20
>> Thank you for this non-complicated answer. :-)
>=20
> I worry about what happens for those people who would be running=20
> FreeBSD on older equipment where polling might still make sense.
>=20
> Do we throw them under the bus?

I think that adding a big fat warning at boot if the driver supports proper h=
ybrid polling (think: witness) might dissuade some folks.
Thanks!
-Garrett=