From owner-freebsd-net@FreeBSD.ORG Sun Sep 13 15:41:48 2009 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 125CD1065676 for ; Sun, 13 Sep 2009 15:41:48 +0000 (UTC) (envelope-from erikt@midgard.homeip.net) Received: from ch-smtp03.sth.basefarm.net (ch-smtp03.sth.basefarm.net [80.76.149.214]) by mx1.freebsd.org (Postfix) with ESMTP id C1B498FC12 for ; Sun, 13 Sep 2009 15:41:47 +0000 (UTC) Received: from c83-255-48-78.bredband.comhem.se ([83.255.48.78]:54697 helo=falcon.midgard.homeip.net) by ch-smtp03.sth.basefarm.net with esmtp (Exim 4.68) (envelope-from ) id 1Mmqy4-00059p-BR for freebsd-net@freebsd.org; Sun, 13 Sep 2009 17:26:22 +0200 Received: (qmail 17725 invoked from network); 13 Sep 2009 17:26:18 +0200 Received: from owl.midgard.homeip.net (10.1.5.7) by falcon.midgard.homeip.net with ESMTP; 13 Sep 2009 17:26:18 +0200 Received: (qmail 1678 invoked by uid 1001); 13 Sep 2009 17:26:18 +0200 Date: Sun, 13 Sep 2009 17:26:18 +0200 From: Erik Trulsson To: rihad Message-ID: <20090913152618.GA1618@owl.midgard.homeip.net> References: <94372.57247.qm@web63906.mail.re1.yahoo.com> <4AAD02A2.5060207@mail.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4AAD02A2.5060207@mail.ru> User-Agent: Mutt/1.5.20 (2009-06-14) X-Originating-IP: 83.255.48.78 X-Scan-Result: No virus found in message 1Mmqy4-00059p-BR. X-Scan-Signature: ch-smtp03.sth.basefarm.net 1Mmqy4-00059p-BR f466fa19f93d4a9ca2062b097e43babc Cc: Barney Cordoba , freebsd-net@freebsd.org Subject: Re: [POLLING] strange interrupt/system load X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 13 Sep 2009 15:41:48 -0000 On Sun, Sep 13, 2009 at 07:33:06PM +0500, rihad wrote: > Barney Cordoba wrote: > > > > --- On Sun, 9/13/09, rihad wrote: > >> What's wrong with 64 bits? > > > > I haven't spent a large portion of my life trying to figure > > it out exactly, but I'd guess that the larger size of the > > structures and code results in fewer cache hits. > > Then what's wrong with also doubling cache sizes? Increasing the size of the CPU cache not only makes it more expensive to manufacture, but also makes it slightly slower to access. > Besides, apart from other benefits, 64-bit makes every-day big number > arithmetic a single CPU instruction as opposed to several instructions > required on 32-bit CPUs through bignum emulation. True, and if you need to perform a lot of 64-bit arithmetic then the extra register width can indeed be a major win. Most people, on most systems, have very limited need of 64-bit arithmetic. -- Erik Trulsson ertr1013@student.uu.se