From owner-freebsd-questions@FreeBSD.ORG Thu Jul 23 12:22:05 2009 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 48993106566C for ; Thu, 23 Jul 2009 12:22:05 +0000 (UTC) (envelope-from rwmaillists@googlemail.com) Received: from ey-out-2122.google.com (ey-out-2122.google.com [74.125.78.27]) by mx1.freebsd.org (Postfix) with ESMTP id BDE318FC1A for ; Thu, 23 Jul 2009 12:22:04 +0000 (UTC) (envelope-from rwmaillists@googlemail.com) Received: by ey-out-2122.google.com with SMTP id 9so233059eyd.7 for ; Thu, 23 Jul 2009 05:22:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:received:received:date:from:to:subject :message-id:in-reply-to:references:x-mailer:mime-version :content-type:content-transfer-encoding; bh=9vtw90/p9sNe7fdLIWxbc7xtibbw0TKIHl88Bf5vDos=; b=tI4TkU4pX8qclsiXG7G216s10PkCOgvat/zRhlk4GFm6F7LhswoEvMMBi0l52rkB+P RtX9XvCPzBHzvgR5wkcFpsV+D1n3BbDETIxUFOKYHr212fz7LyjAJdUrEzZEjrFtt5kN 8AFMhMktDyAj8rUMvqOCRLTOafUNOpyRmU4Nc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=date:from:to:subject:message-id:in-reply-to:references:x-mailer :mime-version:content-type:content-transfer-encoding; b=Ol+Ktd+Cdlz8QFvGbUuun1ktCQQ6A+L7r5JmtTO34GMRObHdvdJxXRJZmvc3lsN4oQ CSV5XD2VYxfvPGdRVhOpgWbP1ndXD1FKMOrYVutS6dIeDUC7olLazow1zNPXGycC2S/3 HwPAEeQ823M0EG/FHawpafUWCmFuQ3Z8nV3m8= Received: by 10.216.54.194 with SMTP id i44mr599582wec.93.1248351723725; Thu, 23 Jul 2009 05:22:03 -0700 (PDT) Received: from gumby.homeunix.com (bb-87-81-140-128.ukonline.co.uk [87.81.140.128]) by mx.google.com with ESMTPS id m5sm4255899gve.3.2009.07.23.05.22.02 (version=SSLv3 cipher=RC4-MD5); Thu, 23 Jul 2009 05:22:03 -0700 (PDT) Date: Thu, 23 Jul 2009 13:22:00 +0100 From: RW To: freebsd-questions@freebsd.org Message-ID: <20090723132200.4cf4002e@gumby.homeunix.com> In-Reply-To: References: <200907221157.n6MBvpKf028533@mp.cs.niu.edu> X-Mailer: Claws Mail 3.7.2 (GTK+ 2.16.5; i386-portbld-freebsd7.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: ULE and Prescott question X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Jul 2009 12:22:05 -0000 On Wed, 22 Jul 2009 22:33:46 +0200 Ivan Voras wrote: > Scott Bennett wrote: > > This is a curiousity question. I'm running 7.2-STABLE at > > present on an old Inspiron XPS, which has a 3.4 GHz P4 Prescott > > CPU. I have hyperthreading enabled in the kernel. The question > > is: is there any appreciable performance difference to be expected > > with this hardware setup between the ULE scheduler and the 4BSD > > scheduler? Or does the fact that there is only one core eliminate > > any difference in performance characteristics? > > I'd guess the second thing. It's not like there's cache to be shared > between cores, etc. But with hyperthreading enabled, don't you have virtual CPUs sharing L1 cache rather that cores sharing L2 cache, making the case for ULE even stronger?