From owner-cvs-src@FreeBSD.ORG  Sat Dec  4 12:27:37 2004
Return-Path: <owner-cvs-src@FreeBSD.ORG>
Delivered-To: cvs-src@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP
	id DC4B016A4CE; Sat,  4 Dec 2004 12:27:37 +0000 (GMT)
Received: from mailout2.pacific.net.au (mailout2.pacific.net.au [61.8.0.85])
	by mx1.FreeBSD.org (Postfix) with ESMTP
	id 2CB3343D1F; Sat,  4 Dec 2004 12:27:37 +0000 (GMT)
	(envelope-from bde@zeta.org.au)
Received: from mailproxy2.pacific.net.au (mailproxy2.pacific.net.au
	[61.8.0.87])iB4CRSKP018366;	Sat, 4 Dec 2004 23:27:28 +1100
Received: from katana.zip.com.au (katana.zip.com.au [61.8.7.246])
	iB4CRP7M017081;	Sat, 4 Dec 2004 23:27:26 +1100
Date: Sat, 4 Dec 2004 23:27:24 +1100 (EST)
From: Bruce Evans <bde@zeta.org.au>
X-X-Sender: bde@delplex.bde.org
To: Alfred Perlstein <alfred@freebsd.org>
In-Reply-To: <20041204075743.GL69608@elvis.mu.org>
Message-ID: <20041204230638.W10805@delplex.bde.org>
References: <20041203120940.5573116A515@hub.freebsd.org>
	<41B091E8.2060807@root.org><20041204075743.GL69608@elvis.mu.org>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
cc: src-committers@freebsd.org
cc: cvs-src@freebsd.org
cc: cvs-all@freebsd.org
cc: Poul-Henning Kamp <phk@freebsd.org>
cc: Nate Lawson <nate@root.org>
cc: Jeff Roberson <jroberson@chesapeake.net>
Subject: Re: cvs commit: src/sys/kern vfs_subr.c
X-BeenThere: cvs-src@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: CVS commit messages for the src tree <cvs-src.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src>,
	<mailto:cvs-src-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/cvs-src>
List-Post: <mailto:cvs-src@freebsd.org>
List-Help: <mailto:cvs-src-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src>,
	<mailto:cvs-src-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 04 Dec 2004 12:27:38 -0000

On Fri, 3 Dec 2004, Alfred Perlstein wrote:

> * Jeff Roberson <jroberson@chesapeake.net> [041203 23:42] wrote:
> > On Fri, 3 Dec 2004, Nate Lawson wrote:
> >
> > > I think that breaking vprint() into multiple lines is not a good idea.
> > > Bruce pointed this out to me when I was doing the v_tag changes a while ago.
> >
> > What's the reason?
>
> possibility of it being non-atomically written to the log files?

The original reason was that log files work best with 1 line per event.
vprint() prints a label, but only for the first line so breaking the
lines breaks grepping for the label...

Atomicity isn't guaranteed, but Ian Dowse made it more likely that
single-line messages are complete if they are logged to disk at all,
by discarding truncated lines.  This doesn't work so well for
incomplete multi-line messages.

Bruce