From owner-freebsd-hackers Fri Jul 13 18: 6:40 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from nwcst320.netaddress.usa.net (nwcst320.netaddress.usa.net [204.68.23.65]) by hub.freebsd.org (Postfix) with SMTP id 8B7D437B401 for ; Fri, 13 Jul 2001 18:06:36 -0700 (PDT) (envelope-from nitinnahata@usa.net) Received: (qmail 14103 invoked by uid 60001); 14 Jul 2001 01:06:36 -0000 Message-ID: <20010714010636.14102.qmail@nwcst320.netaddress.usa.net> Received: from 204.68.23.65 by nwcst320 for [128.9.112.66] via web-mailer(34FM.0700.18.03B) on Sat Jul 14 01:06:35 GMT 2001 Date: 13 Jul 2001 18:06:35 PDT From: Nitin Nahata To: freebsd-hackers@freebsd.org Subject: Re: [Re: Block Device I/O] X-Mailer: USANET web-mailer (34FM.0700.18.03B) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Julian Elischer wrote: > we couldn't find any reason th have block devices except in teh case fo= r > exporting the nodes via NFS. = > = > The buffer caching is done at teh filesystem level, and raw-io is faste= r > with the raw device, so it was complicating the code without giving us = any > real advantage.. If you need a cached device then you can achieve that = in > other ways. > your comments are appreciated.. > = > = Are there any documents/papers available regarding the current I/O implementation because I am having a little difficulty in understanding how things are working below the vnode/vfs layer? = Thanks, Nitin = > On 13 Jul 2001, Nitin Nahata wrote: > = > > I saw an old message in 1999 freebsd-hackers archive that said that b= lock > > devices were being replaced from freebsd. I tried to follow the trail= of > > the message but could not find anything more.......Also I could not f= ind > > any bdevsw[] in the code. I shall be thankful if anyone could give an= y > > further references about how Block I/O is being implemented now... > > = > > Thanks > > = > > Nitin = > > = > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-hackers" in the body of the message > > = > = > = > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-hackers" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message