From owner-freebsd-arch@FreeBSD.ORG Sun Mar 22 15:54:29 2015 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 561054BB for ; Sun, 22 Mar 2015 15:54:29 +0000 (UTC) Received: from mailout.easymail.ca (mailout.easymail.ca [64.68.201.169]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 0D10EF6F for ; Sun, 22 Mar 2015 15:54:28 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mailout.easymail.ca (Postfix) with ESMTP id 01137E60A for ; Sun, 22 Mar 2015 11:47:45 -0400 (EDT) X-Virus-Scanned: Debian amavisd-new at mailout.easymail.ca X-Spam-Flag: NO X-Spam-Score: -3.839 X-Spam-Level: X-Spam-Status: No, score=-3.839 required=5 tests=[ALL_TRUSTED=-1.8, AWL=-0.132, BAYES_00=-2.599, DNS_FROM_AHBL_RHSBL=0.692] Received: from mailout.easymail.ca ([127.0.0.1]) by localhost (easymail-mailout.easydns.vpn [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YONMq3+I+2gn for ; Sun, 22 Mar 2015 11:47:44 -0400 (EDT) Received: from bsddt1241.lv01.astrodoggroup.com (unknown [40.141.24.126]) (using TLSv1 with cipher DHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by mailout.easymail.ca (Postfix) with ESMTPSA id 530DEE5B4 for ; Sun, 22 Mar 2015 11:47:44 -0400 (EDT) Message-ID: <550EDF87.2070101@astrodoggroup.com> Date: Sun, 22 Mar 2015 08:28:07 -0700 From: Harrison Grundy User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-Version: 1.0 To: freebsd-arch@freebsd.org Subject: Re: RFC: Simplfying hyperthreading distinctions References: <1640664.8z9mx3EOQs@ralph.baldwin.cx> <54FA1180.3080605@astrodoggroup.com> <1526311.uylCbgv5VB@ralph.baldwin.cx> <20150320123823.GA49621@zxy.spb.ru> <550DC564.5020802@freebsd.org> <20150321214336.334eaea5@nonamehost.local> <20150322100744.5b390591@ernst.home> In-Reply-To: <20150322100744.5b390591@ernst.home> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Mar 2015 15:54:29 -0000 On 03/22/15 02:07, Gary Jennejohn wrote: > On Sat, 21 Mar 2015 21:43:35 +0200 > Ivan Klymenko wrote: > >> __ Sat, 21 Mar 2015 12:24:20 -0700 >> Alfred Perlstein __________: >> >>> John, >>> >>> Just a quick note on this, hopefully it's not too off-topic... >>> >>> We need to detect if HTT or SMT is enabled, right now there are no >>> sysctl nodes to detect this and instead we have to parse xml out of >>> the scheduler... >>> >>> Does it make sense to have a basic sysctl tree for this? >>> >>> hw.cpu.threading.smt=0 >>> hw.cpu.threading.htt=0 >>> >>> or something? >>> >> >> I am sorry that I interfere >> Why then not use kern.smp.topology for this purpose? >> > > Because it's only present in the ULE scheduler, BSD doesn't > have it. > Extracting topology detection out of the scheduler and finalizing that API may be a good idea anyway, given the NUMA work going on elsewhere. Things besides the scheduler can benefit from the information, and it'll simplify the scheduler a bit. Any thoughts on handling it that way? --- Harrison