From owner-freebsd-sparc64@FreeBSD.ORG  Thu Nov 30 22:31:37 2006
Return-Path: <owner-freebsd-sparc64@FreeBSD.ORG>
X-Original-To: freebsd-sparc64@freebsd.org
Delivered-To: freebsd-sparc64@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 9513616A412
	for <freebsd-sparc64@freebsd.org>; Thu, 30 Nov 2006 22:31:37 +0000 (UTC)
	(envelope-from kris@obsecurity.org)
Received: from elvis.mu.org (elvis.mu.org [192.203.228.196])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 863A743CAA
	for <freebsd-sparc64@freebsd.org>; Thu, 30 Nov 2006 22:31:16 +0000 (GMT)
	(envelope-from kris@obsecurity.org)
Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196])
	by elvis.mu.org (Postfix) with ESMTP id A9B091A4D87;
	Thu, 30 Nov 2006 14:31:26 -0800 (PST)
Received: by obsecurity.dyndns.org (Postfix, from userid 1000)
	id 3374451316; Thu, 30 Nov 2006 17:31:08 -0500 (EST)
Date: Thu, 30 Nov 2006 17:31:08 -0500
From: Kris Kennaway <kris@obsecurity.org>
To: Miles Nordin <carton@Ivy.NET>
Message-ID: <20061130223107.GA61593@xor.obsecurity.org>
References: <755cb9fc0611290724q127f006va84f3457c48443b6@mail.gmail.com>
	<oq8xht7biy.fsf@castrovalva.Ivy.NET> <456E8D8B.8010102@orel.ru>
	<755cb9fc0611300454s4d28ad14rd402cba8388d49@mail.gmail.com>
	<14989d6e0611300700n3ac073bayc4584f2b1020ee61@mail.gmail.com>
	<755cb9fc0611300839y6deed1ceqf452018cc2f73737@mail.gmail.com>
	<oqzma869j9.fsf@castrovalva.Ivy.NET>
	<755cb9fc0611301208w1ff93987m88885b3b59444373@mail.gmail.com>
	<oqvekw609g.fsf@castrovalva.Ivy.NET>
Mime-Version: 1.0
Content-Type: multipart/signed; micalg=pgp-sha1;
	protocol="application/pgp-signature"; boundary="6c2NcOVqGQ03X4Wi"
Content-Disposition: inline
In-Reply-To: <oqvekw609g.fsf@castrovalva.Ivy.NET>
User-Agent: Mutt/1.4.2.2i
Cc: freebsd-sparc64@freebsd.org
Subject: Re: Netra T1 105 (sparc64) optimization
X-BeenThere: freebsd-sparc64@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Porting FreeBSD to the Sparc <freebsd-sparc64.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-sparc64>, 
	<mailto:freebsd-sparc64-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-sparc64>
List-Post: <mailto:freebsd-sparc64@freebsd.org>
List-Help: <mailto:freebsd-sparc64-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-sparc64>,
	<mailto:freebsd-sparc64-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 30 Nov 2006 22:31:37 -0000


--6c2NcOVqGQ03X4Wi
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Thu, Nov 30, 2006 at 05:24:43PM -0500, Miles Nordin wrote:
> >>>>> "av" =3D=3D Alexandre Vieira <nullpt@gmail.com> writes:
>=20
>     av> Without polling it transfers like 8MB/s, with polling it does
>     av> less than this and there is twice the latency.
>=20
> that's not what i expected on both counts.
>=20
> but the supposed benefit of polling is increase in pps capacity, not
> reduced latency.

sparc64 doesn't do preemption, so interrupt latency is longer than it
should be.  Presumably that is why polling helps so much.

Kris

--6c2NcOVqGQ03X4Wi
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.5 (FreeBSD)

iD8DBQFFb1urWry0BWjoQKURAmh8AKCbh5NUeUZI0spuY5CGYNqVxVzgUQCgsXSL
kiqIvDS9HdPCPoM7PScb5mQ=
=RQCs
-----END PGP SIGNATURE-----

--6c2NcOVqGQ03X4Wi--