From owner-freebsd-hackers Mon Jan 26 23:08:48 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id XAA26348 for hackers-outgoing; Mon, 26 Jan 1998 23:08:48 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from word.smith.net.au (vh1.gsoft.com.au [203.38.152.122]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id XAA26295 for ; Mon, 26 Jan 1998 23:08:42 -0800 (PST) (envelope-from mike@word.smith.net.au) Received: from word (localhost [127.0.0.1]) by word.smith.net.au (8.8.8/8.8.5) with ESMTP id RAA01893; Tue, 27 Jan 1998 17:18:57 +1030 (CST) Message-Id: <199801270648.RAA01893@word.smith.net.au> X-Mailer: exmh version 2.0zeta 7/24/97 To: "Daniel O'Connor" cc: joelh@gnu.org, mike@smith.net.au, dag-erli@ifi.uio.no, hackers@FreeBSD.ORG Subject: Re: File I/O in kernel land (was: Re: 2nd warning: 2.2.6 BETA begins in 10 days!) In-reply-to: Your message of "Tue, 27 Jan 1998 17:21:32 +1030." <199801270651.RAA29592@cain.gsoft.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 27 Jan 1998 17:18:56 +1030 From: Mike Smith Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk > > > My real concern is holding on to lots of dynamically allocated kernel > > memory, which is something I can't see getting around without the > > screen saver doing file I/O. In Linux, dynamic kernel memory was a > > precious resource. Is it not so in FreeBSD? > Umm, well wouldn't it be allocated in either case? > You either load it in the kernel, or you load it in user land, and then copy > it to the kernel.. You still take kernel memory to do it. Actually, if you're a real stud, you hold an open vnode reference on it, and read it off the disk every time you want to display it. As Julian said, see how the code in the kernel handles reading executable images. It's moderately painful, but definitely the Right Way to do it. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\