From owner-freebsd-stable@FreeBSD.ORG Wed Apr 25 12:50:20 2007 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 0146A16A406 for ; Wed, 25 Apr 2007 12:50:20 +0000 (UTC) (envelope-from matrix@itlegion.ru) Received: from corpmail.itlegion.ru (corpmail.itlegion.ru [84.21.226.211]) by mx1.freebsd.org (Postfix) with SMTP id 3092113C484 for ; Wed, 25 Apr 2007 12:50:18 +0000 (UTC) (envelope-from matrix@itlegion.ru) Received: (qmail 84707 invoked from network); 25 Apr 2007 16:50:17 +0400 Received: from unknown (HELO Artem) (192.168.0.12) by 84.21.226.211 with SMTP; 25 Apr 2007 16:50:17 +0400 X-AntiVirus: Checked by Dr.Web [version: 4.33, engine: 4.33.5.10110, virus records: 196263, updated: 25.04.2007] Message-ID: <026301c78738$460bdf50$0c00a8c0@Artem> From: "Artem Kuchin" To: "Richard Tector" References: <00e301c7872d$03e1db80$0c00a8c0@Artem> <462F3E60.7010109@thekeelecentre.com> Date: Wed, 25 Apr 2007 16:50:13 +0400 Organization: IT Legion MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset="koi8-r"; reply-type=response Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 Cc: freebsd-stable@freebsd.org Subject: Re: Top not showing 4 cpus on 2 xeons with HT X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Apr 2007 12:50:20 -0000 Richard Tector wrote: > Artem Kuchin wrote: >> I am just wondering if it is normal. >> I have two xeon processors with HT on each of them. >> When loading kernel says that 4 cpu's are found, >> but when i do top i can see only 0 or 2 in the C >> column. never 1 or 3. Is it normal? >> >> FreeBSD 6.2-STABLE (cvsed 1 day ago) > If I remember correctly, HT is disabled by default for security > reasons but there should be a sysctl to enable it. I believe there is > also a paper by Colin Percival on the issue. ahh, heck, i'll take my chances. I've read the paper and the attack seem to me almost unreal. Also, everybody is in the jail on the server. > Note that in a lot of common loads, the use of HT with the standard > scheduler does not yield any real benefits. Hmm. I just turned it on and already see that hosts are running generally faster (it is a hosting server, 100+ site). No numbers though. It just *SEEMS* faster. Anyway, it cannot make thing slower for sure, or can it? -- Regards, Artem