From owner-freebsd-arch@FreeBSD.ORG Wed Dec 19 17:23:28 2012 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 42F37563; Wed, 19 Dec 2012 17:23:28 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) by mx1.freebsd.org (Postfix) with ESMTP id 9C6E78FC0A; Wed, 19 Dec 2012 17:23:27 +0000 (UTC) Received: from tom.home (kostik@localhost [127.0.0.1]) by kib.kiev.ua (8.14.5/8.14.5) with ESMTP id qBJHNKI9047899; Wed, 19 Dec 2012 19:23:20 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.7.3 kib.kiev.ua qBJHNKI9047899 Received: (from kostik@localhost) by tom.home (8.14.5/8.14.5/Submit) id qBJHNKcl047898; Wed, 19 Dec 2012 19:23:20 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Wed, 19 Dec 2012 19:23:20 +0200 From: Konstantin Belousov To: Poul-Henning Kamp Subject: Re: Unmapped I/O Message-ID: <20121219172320.GW71906@kib.kiev.ua> References: <20121219135451.GU71906@kib.kiev.ua> <50D1D2BD.80107@freebsd.org> <50D1ECC5.2070209@freebsd.org> <17252.1355935960@critter.freebsd.dk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="25+pmc5/5D73GfAV" Content-Disposition: inline In-Reply-To: <17252.1355935960@critter.freebsd.dk> User-Agent: Mutt/1.5.21 (2010-09-15) X-Spam-Status: No, score=-2.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FROM,NML_ADSP_CUSTOM_MED autolearn=no version=3.3.2 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on tom.home Cc: mjacob@freebsd.org, freebsd-arch@freebsd.org X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Dec 2012 17:23:28 -0000 --25+pmc5/5D73GfAV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Dec 19, 2012 at 04:52:40PM +0000, Poul-Henning Kamp wrote: > -------- > In message <50D1ECC5.2070209@freebsd.org>, Julian Elischer writes: >=20 > >yeah.. Bill Jolitz had patches for this in 92 ... that disappeared=20 > >with him. >=20 > You know, I've never seen a shred of evidence supporting that claim > or any of the many similarly improbable claims Bill Jolitz made, and > in this particular case I very much did look for such evidence. This is definitely not a discussion I hoped for. Still, the i386 cannot have much benefit from the unmapped buffers, just because thre is no facilities similar to the direct map for amd64. i386 must use transient mapping even for unmapped buffers to copy the data to the usermode. Also, as I understand the history, VMIO buffers, or unified page/buffer cache, only appeared in the FreeBSD. --25+pmc5/5D73GfAV Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iQIcBAEBAgAGBQJQ0fgIAAoJEJDCuSvBvK1BMj8P/Au3nPzZZgXNjSEVpxSQ8gjD Wj3sr1XdtTuz3Y4lhmE6XLSy7mHyeS1HtNeoSSqZktHuteUE4DmtgyMuscHe+de+ heBQ7eob1sG7N363dibIUHMhkkWe/MZX8YZ50Jp/p13ij2ME4Um+jWtFVyn1VGNj 6hbH2uq0ClSYV9yI3iE+TJReWIeTfrSpNL535rGb7zoY7xlQh0LW74m0E7OE0/E+ oIaphXOkOn1OjL5PhYqX0TXeU+IB4vAxNPJmeetj8h9anWj8J+wMdP3s9Ki6xEwu dfj2ul0R2ddGG1Kkz+Dh3/22EXlpJIj2ahOkcRQkLB+K0PST3PGj7NQDnysh/bab OVCLc/o5S3t5LH4AF4LAsYc4OYrlkgVUx8O/AUoNSrZBZHu3RbxcSv3+FoQ3Dd9v UwqNkzuMPm6W8ZggJiiSZ6nwqR4Xc2EN6R+6qoI9fT3D6nPwcANDHOeOd/Xk7fz0 ntKgotw6zZtHjjpB7j3rJ243WgjNLJntYHfcvathCkD88IprLaLIU2RSMU8p6JRN mbBa7Mq4ksNVvDO+zaQz+8PawdkEaQv7mMsI/SP1owPU4uVCvJaOaEi5CIdumHum +BMj6bMBShkiZLjZUBx3hjdElU9SrGr+HYskWx0CPQP9X/n1FWejq98pKXfy2h22 eKRpEhjrmnpScYOcZEUg =FEJY -----END PGP SIGNATURE----- --25+pmc5/5D73GfAV--