From owner-cvs-all@FreeBSD.ORG Mon Aug 16 05:34:56 2004 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B40A116A4CE; Mon, 16 Aug 2004 05:34:56 +0000 (GMT) Received: from mail2.dreamscape.com (mail2.dreamscape.com [206.64.128.18]) by mx1.FreeBSD.org (Postfix) with ESMTP id 37B7243D41; Mon, 16 Aug 2004 05:34:56 +0000 (GMT) (envelope-from krentel@dreamscape.com) Received: from blue.mwk.domain (sA17-p49.dreamscape.com [209.217.195.240]) i7G5Yp2U024344; Mon, 16 Aug 2004 01:34:52 -0400 (EDT) Received: from blue.mwk.domain (localhost [127.0.0.1]) by blue.mwk.domain (8.12.9p2/8.12.9) with ESMTP id i7G5drJE018193; Mon, 16 Aug 2004 01:39:53 -0400 (EDT) (envelope-from krentel@blue.mwk.domain) Message-Id: <200408160539.i7G5drJE018193@blue.mwk.domain> To: des@des.no, cvs-all@FreeBSD.org Date: Mon, 16 Aug 2004 01:39:53 -0400 From: "Mark W. Krentel" cc: alc@FreeBSD.org Subject: Re: cvs commit: src/sys/vm vm_map.c vm_map.h X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Aug 2004 05:34:56 -0000 > Great! I've been meaning to do this for a while, but the complexity > was a bit beyond me. This should greatly increase pipe performance, > by the way, because pipe buffers are allocated from a single vm_map, > which accumulates many more entries and much more fragmentation than > (probably) most other maps in the kernel. If you (or anyone else) have a real-world application that runs measurably better with the new vm_map_findspace() algorithm, I'd love to hear about it, especially if you have numbers. Probably on -hackers or something. I can write a one-page C program that mmap()'s many pages with holes between them that is a factor of 50-100 faster with the new algorithm where "many" is around 10,000. But it's a very artificial micro- benchmark. --Mark