From owner-freebsd-hackers@FreeBSD.ORG Tue Jan 22 15:04:10 2008 Return-Path: Delivered-To: freebsd-hackers@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2124116A417 for ; Tue, 22 Jan 2008 15:04:10 +0000 (UTC) (envelope-from stefan.lambrev@moneybookers.com) Received: from blah.sun-fish.com (blah.sun-fish.com [217.18.249.150]) by mx1.freebsd.org (Postfix) with ESMTP id D789F13C457 for ; Tue, 22 Jan 2008 15:04:09 +0000 (UTC) (envelope-from stefan.lambrev@moneybookers.com) Received: by blah.sun-fish.com (Postfix, from userid 1002) id 7214A1B10EBB; Tue, 22 Jan 2008 16:04:08 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on blah.cmotd.com X-Spam-Level: X-Spam-Status: No, score=-10.3 required=5.0 tests=ALL_TRUSTED,BAYES_00, MIME_8BIT_HEADER autolearn=no version=3.2.3 Received: from hater.haters.org (hater.cmotd.com [192.168.3.125]) by blah.sun-fish.com (Postfix) with ESMTP id 500681B10ED2; Tue, 22 Jan 2008 16:04:02 +0100 (CET) Message-ID: <479605E2.6070709@moneybookers.com> Date: Tue, 22 Jan 2008 17:04:02 +0200 From: Stefan Lambrev User-Agent: Thunderbird 2.0.0.9 (X11/20071120) MIME-Version: 1.0 To: =?UTF-8?B?RGFnLUVybGluZyBTbcO4cmdyYXY=?= References: <4795CC13.7080601@moneybookers.com> <868x2i3v8d.fsf@ds4.des.no> <864pd63v2h.fsf@ds4.des.no> <4795FE54.9090606@moneybookers.com> <86lk6i0vzk.fsf@ds4.des.no> In-Reply-To: <86lk6i0vzk.fsf@ds4.des.no> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Virus-Scanned: ClamAV 0.91.2/5520/Tue Jan 22 14:09:49 2008 on blah.cmotd.com X-Virus-Status: Clean Cc: freebsd-hackers@FreeBSD.org Subject: Re: gettimeofday() in hping X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 22 Jan 2008 15:04:10 -0000 Hi, Dag-Erling Sm=C3=B8rgrav wrote: > Stefan Lambrev writes: > =20 >> I tested all different combination. The performance change is almost >> invisible (100-200KB/s), and can't be compared with the performance >> boost that TSC gain over ACPI-fast timecounter. Unfortunately TSC >> doesn't play nice with power saving modes. >> =20 > > This will vary greatly from machine to machine, depending on the exact > hardware and the ACPI BIOS. > > More modern machines have an HPET timer which is supposedly faster than= > ACPI yet more reliable than TSC. > > DES > =20 I do not have HEPT on the servers that I test, but simple test on my=20 laptop shows that hping can generate with ACPI-fast ~4MB/s traffic, 5MB/s with HPET and 8MB/s with TSC. I didn't check dummy time counter. Also I noticed that there is a kern.timecounter.tc.XXX.quality (read only= ). Can this be used to reduce quality and speed up performance? --=20 Best Wishes, Stefan Lambrev ICQ# 24134177