From owner-freebsd-hackers@FreeBSD.ORG Tue Oct 26 23:32:35 2010 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4B6E11065670; Tue, 26 Oct 2010 23:32:35 +0000 (UTC) (envelope-from bruce@cran.org.uk) Received: from muon.cran.org.uk (muon.cran.org.uk [IPv6:2a01:348:0:15:5d59:5c40:0:1]) by mx1.freebsd.org (Postfix) with ESMTP id 1199D8FC12; Tue, 26 Oct 2010 23:32:35 +0000 (UTC) Received: from muon.cran.org.uk (localhost [127.0.0.1]) by muon.cran.org.uk (Postfix) with ESMTP id 60BABE801E; Wed, 27 Oct 2010 00:32:34 +0100 (BST) Received: from unknown (client-81-107-142-135.midd.adsl.virginmedia.com [81.107.142.135]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by muon.cran.org.uk (Postfix) with ESMTPSA; Wed, 27 Oct 2010 00:32:33 +0100 (BST) Date: Wed, 27 Oct 2010 00:32:29 +0100 From: Bruce Cran To: Alexander Best Message-ID: <20101027003229.00002b91@unknown> In-Reply-To: <20101026213618.GA3013@freebsd.org> References: <20101026213618.GA3013@freebsd.org> X-Mailer: Claws Mail 3.7.6 (GTK+ 2.16.6; i586-pc-mingw32msvc) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: freebsd-hackers@freebsd.org Subject: Re: fsync(2) manual and hdd write caching X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Oct 2010 23:32:35 -0000 On Tue, 26 Oct 2010 21:36:18 +0000 Alexander Best wrote: > since there's a thread on freebsd-questions@ concerning fsync(2) and > the fact that hdd write caching can cause this syscall to basically > be a no op, could somebody please copy the BUGS section from sync(2) > to fsync(2)? Shouldn't the BUGS section of sync(2) be removed? "The sync() system call may return before the buffers are completely flushed." But from http://www.opengroup.org/onlinepubs/009695399/functions/sync.html : "The writing, although scheduled, is not necessarily complete upon return from sync()." That would suggest it's not actually a bug. -- Bruce Cran