From owner-freebsd-hackers Tue Dec 15 10:01:33 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id KAA28608 for freebsd-hackers-outgoing; Tue, 15 Dec 1998 10:01:33 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from bright.fx.genx.net (bright.fx.genx.net [206.64.4.154]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id KAA28539 for ; Tue, 15 Dec 1998 10:01:31 -0800 (PST) (envelope-from bright@hotjobs.com) Received: from localhost (bright@localhost) by bright.fx.genx.net (8.9.1/8.9.1) with ESMTP id NAA03138; Tue, 15 Dec 1998 13:05:43 -0500 (EST) (envelope-from bright@hotjobs.com) X-Authentication-Warning: bright.fx.genx.net: bright owned process doing -bs Date: Tue, 15 Dec 1998 13:05:43 -0500 (EST) From: Alfred Perlstein X-Sender: bright@bright.fx.genx.net To: John Polstra cc: eivind@yes.no, hackers@FreeBSD.ORG Subject: Re: idea/help w. mirroring In-Reply-To: <199812151753.JAA16545@vashon.polstra.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 15 Dec 1998, John Polstra wrote: > In article <19981214232905.R5444@follo.net>, > Eivind Eklund wrote: > > On Mon, Dec 14, 1998 at 04:39:42PM -0500, Alfred Perlstein wrote: > > > > > > Has anyone written something that could be used to intercept all calls to > > > write out file modification and give the modifications to a userland > > > application? > > > > > > I'm interested in the most efficient method of doing filesystem mirroring, > > > passing that info into a userland app using multicast would be ideal. > > > > > > The userland app may see which blocks of which file have been modified and > > > distribute deltas across the network. > > Something like that would also be useful to reduce the load on > primary CVSup server hosts such as freefall. anything dealing with deltas would work much fast with this. > > > Stacking layer. > > Ha ha ha, how about something that actually works, as opposed to > "sounds good in the McKusick book"? As far as I can tell, there's not > a single stackable filesystem in FreeBSD that works well enough to use > in practice. I was thinking of intercepting the calls to actually write out data, however i think that by that point we are mapped to a physical address on the disk/media and not a logical block within a file. :/ I really need to read more kernel code. Our 'stacking' does work afaik? just no facilities for callbacks on a local filesystem right? Alfred Perlstein - Programmer, HotJobs Inc. - www.hotjobs.com -- There are operating systems, and then there's FreeBSD. -- http://www.freebsd.org/ 3.0-current > John > -- > John Polstra jdp@polstra.com > John D. Polstra & Co., Inc. Seattle, Washington USA > "Nobody ever went broke underestimating the taste of the American public." To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message