From owner-freebsd-hackers Thu Oct 21 16:34:37 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from fw.wintelcom.net (ns1.wintelcom.net [209.1.153.20]) by hub.freebsd.org (Postfix) with ESMTP id 0370314D2D for ; Thu, 21 Oct 1999 16:34:31 -0700 (PDT) (envelope-from bright@wintelcom.net) Received: from localhost (bright@localhost) by fw.wintelcom.net (8.9.3/8.9.3) with ESMTP id QAA25742; Thu, 21 Oct 1999 16:56:01 -0700 (PDT) Date: Thu, 21 Oct 1999 16:56:01 -0700 (PDT) From: Alfred Perlstein To: Zhihui Zhang Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Optimization done in TCP/IP stack In-Reply-To: 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 Thu, 21 Oct 1999, Zhihui Zhang wrote: > > I have put all distribution files on a machine and installed three PCs via > FTP from that machine. The installation process should access the same > files, the buffer cache can be used to improve effieciency on the > filesystem side. I am wondering whether some sort of optimization is done > on the TCP/IP side in this situation. Do we have to copy data from > buffer-cache to mbuf each time we need to send the data over network? As > far as I know, the buffer cache has identity associated with it (vnode, > block #), but the mbuf does not. > > Any help is appreciated. You can use "sendfile" to accomplish zero copy file transfer. -Alfred To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message