Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 06 Nov 2012 10:46:28 +0000
From:      "Poul-Henning Kamp" <phk@phk.freebsd.dk>
To:        Andre Oppermann <andre@freebsd.org>
Cc:        Davide Italiano <davide@freebsd.org>, Ryan Stone <rysto32@gmail.com>, Joe Holden <lists@rewt.org.uk>, Luigi Rizzo <rizzo@iet.unipi.it>, FreeBSD Current <current@freebsd.org>
Subject:   Re: polling's future [was: Re: Dynamic Ticks/HZ]
Message-ID:  <10890.1352198788@critter.freebsd.dk>
In-Reply-To: <5098E8B4.5040309@freebsd.org>
References:  <509758B8.1000409@rewt.org.uk> <CACYV=-HwJ1j2-zDtCtuGNKzdFRJhPsZm6vtFXAVyPSabCXvFEQ@mail.gmail.com> <50975F6F.6010907@rewt.org.uk> <CACYV=-Ef5ij7%2BgqDV9oS3xRyD6Yy2mqDyKqqUZZQ-KsWb_3C3A@mail.gmail.com> <5097898C.9080109@rewt.org.uk> <CAFMmRNwR_XxjnRZvxqew77qNnOTGWrRQnhJkg4u2berL8VCVtw@mail.gmail.com> <20121105163654.GA12870@onelab2.iet.unipi.it> <5097E880.8010001@rewt.org.uk> <20121105165748.GA13098@onelab2.iet.unipi.it> <5098E526.6070101@freebsd.org> <10806.1352197657@critter.freebsd.dk> <5098E8B4.5040309@freebsd.org>

next in thread | previous in thread | raw e-mail | index | archive | help
--------
In message <5098E8B4.5040309@freebsd.org>, Andre Oppermann writes:

>> I think it should go away, and if there still is a relevant
>> usage segment, be replaced by _real_ "device-polling" which is
>> not tied to the network stack.
>
>Don't we already have the equivalent with a fast interrupt thread
>that simply acknowledges and disables the interrupt [...]

The point is that not all hardware have interrupt-pacing, so
being able to poll at a lower rate in software would save overhead.

I'm not sure if the hardware where this applies is still relevant,
it would probably be mostly in the embedded space.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?10890.1352198788>