From owner-freebsd-hackers Mon Feb 7 14:35:45 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from ind.alcatel.com (postal.xylan.com [208.8.0.248]) by builder.freebsd.org (Postfix) with ESMTP id 8149A40BD for ; Mon, 7 Feb 2000 14:35:17 -0800 (PST) Received: from mailhub.xylan.com (mailhub [198.206.181.70]) by ind.alcatel.com (8.9.3+Sun/8.9.1 (ind.alcatel.com 3.0 [OUT])) with SMTP id OAA03016; Mon, 7 Feb 2000 14:35:12 -0800 (PST) X-Origination-Site: Received: from omni.xylan.com by mailhub.xylan.com (SMI-8.6/SMI-SVR4 (mailhub 2.1 [HUB])) id OAA03580; Mon, 7 Feb 2000 14:35:09 -0800 Received: from softweyr.com (dyn5.utah.xylan.com [198.206.184.241]) by omni.xylan.com (8.9.3+Sun/8.9.1 (Xylan engr [SPOOL])) with ESMTP id OAA06275; Mon, 7 Feb 2000 14:35:04 -0800 (PST) Message-ID: <389F49F7.7290B179@softweyr.com> Date: Mon, 07 Feb 2000 15:40:55 -0700 From: Wes Peters Organization: Softweyr LLC X-Mailer: Mozilla 4.7 [en] (X11; U; FreeBSD 3.3-RELEASE i386) X-Accept-Language: en MIME-Version: 1.0 To: Alfred Perlstein Cc: Matthew Dillon , hackers@freebsd.org Subject: Re: Syncing a vector of fileoffsets and lengths? References: <20000207114042.E25520@fw.wintelcom.net> <200002071938.LAA50114@apollo.backplane.com> <20000207125636.G25520@fw.wintelcom.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Alfred Perlstein wrote: > > I asked this question because of a problem that Postgresql has, > basically multiple processes will be updating a file, they may do > scattered IO to multiple offsets into the file, at the end of a > transaction they want to sync the data... fsync(). ow. This causes > buffers dirtied from multiple processes to be pushed to disk where > they really only want thier own. The order doesn't really matter, > just that all of the IO is on stable storage. So, what you're looking for is something like writev, only having the vector entries consist of (fd, pos, nbytes) triples? And perhaps a sync vs. async flag on the call? -- "Where am I, and what am I doing in this handbasket?" Wes Peters Softweyr LLC wes@softweyr.com http://softweyr.com/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message