Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 24 Jul 2001 16:28:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 24 Jul 2001 16:28:10 -0400 Received: from moutvdom00.kundenserver.de ([195.20.224.149]:18525 "EHLO moutvdom00.kundenserver.de") by vger.kernel.org with ESMTP id ; Tue, 24 Jul 2001 16:27:54 -0400 Content-Type: text/plain; charset=US-ASCII From: Patrick Dreker Organization: Chaos Inc. To: Linus Torvalds , phillips@bonn-fries.net, linux-kernel@vger.kernel.org Subject: Re: [RFC] Optimization for use-once pages Date: Tue, 24 Jul 2001 22:24:17 +0200 X-Mailer: KMail [version 1.2.9] In-Reply-To: <200107241648.f6OGmqp29445@penguin.transmeta.com> In-Reply-To: <200107241648.f6OGmqp29445@penguin.transmeta.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Message-Id: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Original-Recipient: rfc822;linux-kernel-outgoing Hello... Am Dienstag, 24. Juli 2001 18:48 schrieb Linus Torvalds: > Please people, test this out extensively - I'd love to integrate it, but > while it looks very sane I'd really like to hear of different peoples > reactions to it under different loads. I just decided to give this patch a try, as I have written a little application which does some statistics over traces dumped by another program by mmap()ing a large file and reading it sequentially. The trace file to be analyzed is about 240 megs in size and consists of records each 249 bytes long. The analysis program opens and the mmap()s the trace file doing some small calculations on the data (basically it adds up fields from the records to get overall values). I have tested this on my Athlon 600 with 128 Megs of RAM, and it does not make any difference whether I use plain 2.4.7 or 2.4.5-use-once. The program always takes about 1 minute 6 seconds (+- 2 seconds) to complete, and the machine starts swapping out stuff (thus I have omitted further stats like vmstat output). I have just taken another look into my program to verify it does not do something silly, like keeping old data around, but the program cycle is always the same: copy a record from the mmap into a struct, perform analysis, and copy next record. The struct is always reused for the next struct (so there is only one struct at any time). I can do further tests, if someone asks me to. I could even modify the analysis program to check changes in behaviour... > Linus Patrick -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/