From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 15 Jan 2001 16:02:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 15 Jan 2001 16:01:51 -0500 Received: from neon-gw.transmeta.com ([209.10.217.66]:28689 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Mon, 15 Jan 2001 16:01:42 -0500 To: linux-kernel@vger.kernel.org From: torvalds@transmeta.com (Linus Torvalds) Subject: Re: Is sendfile all that sexy? Date: 15 Jan 2001 13:00:41 -0800 Organization: Transmeta Corporation Message-ID: <93vodp$bvf$1@penguin.transmeta.com> In-Reply-To: <200101152033.f0FKXpv250839@saturn.cs.uml.edu> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In article <200101152033.f0FKXpv250839@saturn.cs.uml.edu>, Albert D. Cahalan wrote: >Ingo Molnar writes: >> On Mon, 15 Jan 2001, Jonathan Thackray wrote: > >>> It's a very useful system call and makes file serving much more >>> scalable, and I'm glad that most Un*xes now have support for it >>> (Linux, FreeBSD, HP-UX, AIX, Tru64). The next cool feature to add to >>> Linux is sendpath(), which does the open() before the sendfile() all >>> combined into one system call. > >Ingo Molnar's data in a nice table: > >open/close 7.5756 microseconds >stat 5.4864 microseconds >write 0.9614 microseconds >read 1.1420 microseconds >syscall 0.6349 microseconds > >Rather than combining open() with sendfile(), it could be combined >with stat(). Note that "fstat()" is fairly low-overhead (unlike "stat()" it obviously doesn't have to parse the name again), so "open+fstat" is quite fine as-is. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/