Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757415AbXLKXlT (ORCPT ); Tue, 11 Dec 2007 18:41:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753597AbXLKXlJ (ORCPT ); Tue, 11 Dec 2007 18:41:09 -0500 Received: from ug-out-1314.google.com ([66.249.92.170]:6707 "EHLO ug-out-1314.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753350AbXLKXlH (ORCPT ); Tue, 11 Dec 2007 18:41:07 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:subject:date:user-agent:cc:references:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:message-id; b=T2VT/WmlR+41rZwerc5hjjG8PkwT034HaY6K0r2Co2L4pDLG3WvQv+/UJ14IUGuxRZ1dWlaeHAe8m9XZNlp1UnxzrdRjPWZdZeQHFbq9xuk+s0DF4b1UEkrdHSsHHiBmN2dri1GZYe3LQWIrl9NhvwYB/EFq3TBX8xH1WpAuVcg= From: Maxim Levitsky To: Rene Herman Subject: Re: [RFT] Port 0x80 I/O speed Date: Wed, 12 Dec 2007 01:40:34 +0200 User-Agent: KMail/1.9.6 Cc: Linux Kernel , dpreed@reed.com, Alan Cox , pavel@ucw.cz, andi@firstfloor.org, rol@as2917.net, Krzysztof Halasa , david@davidnewall.com, hpa@zytor.com, john@stoffel.org, linux-os@analogic.com References: <475F1DC6.5090403@keyaccess.nl> In-Reply-To: <475F1DC6.5090403@keyaccess.nl> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200712120140.34697.maximlevitsky@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1717 Lines: 54 On Wednesday 12 December 2007 01:31:18 Rene Herman wrote: > Good day. > > Would some people on x86 (both 32 and 64) be kind enough to compile and run > the attached program? This is about testing how long I/O port access to port > 0x80 takes. It measures in CPU cycles so CPU speed is crucial in reporting. > > Posted a previous incarnation of this before, buried in the outb 0x80 thread > which had a serialising problem. This one should as far as I can see measure > the right thing though. Please yell if you disagree... > > For me, on a Duron 1300 (AMD756 chipset) I have a constant: > > rene@7ixe4:~/src/port80$ su -c ./port80 > cycles: out 2400, in 2400 > > and on a PII 400 (Intel 440BX chipset) a constant: > > rene@6bap:~/src/port80$ su -c ./port80 > cycles: out 553, in 251 > > Results are (mostly) independent of compiler optimisation, but testing with > an -O2 compile should be most useful. Thanks! > > Rene. > Sure, maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1767, in 1147 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1774, in 1148 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1769, in 1150 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1769, in 1150 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1777, in 1150 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1766, in 1149 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1768, in 1148 maxim@MAIN:~/tmp$ sudo ./port800 cycles: out 1765, in 1147 Core 2 Duo system (ICH8/Intel DG965RY motherboard) -- 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/