From owner-freebsd-current@FreeBSD.ORG Sun May 31 03:55:22 2009 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 99E34106566C; Sun, 31 May 2009 03:55:22 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: from yw-out-2324.google.com (yw-out-2324.google.com [74.125.46.29]) by mx1.freebsd.org (Postfix) with ESMTP id 36B118FC0C; Sun, 31 May 2009 03:55:21 +0000 (UTC) (envelope-from mat.macy@gmail.com) Received: by yw-out-2324.google.com with SMTP id 9so3691350ywe.13 for ; Sat, 30 May 2009 20:55:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=1MltuZKN4yjeAEcteP6FvknHBWAKclV6TLI8xHhE4Ds=; b=euOzr+dKzFGXikSBjrGNFEAL+3kFUQ+35ktxCRtWqTxIoWaT0mLwy4PMCjAvR+++w0 TViDsEK6I0SGEM8ZhK5jj5XZjGgkLvOiQLmTJcGghHhrLc3K56gT5sWRpissqnxueMII BUS+5R9+HmSQBxebroIluMa6zu7xwGlyul/eA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=L8qDLOsDJIkDQ/IWKcoxgAspxD3IzK6diqO8iBF7UZBJX96cga4LliLQ7KVpSpvYrH 8ojgx7b4FxMw+BbTthg8s18COl8SInnF7FygnpcV3Z64Jg0UFHzSLJn1vIucmTLXjy03 Oj0htSdybTU2e2zlxfiat/IdPnF5jm0yJ4pKI= MIME-Version: 1.0 Sender: mat.macy@gmail.com Received: by 10.100.154.17 with SMTP id b17mr5723386ane.45.1243742121430; Sat, 30 May 2009 20:55:21 -0700 (PDT) In-Reply-To: <951233.95131.qm@web39108.mail.mud.yahoo.com> References: <951233.95131.qm@web39108.mail.mud.yahoo.com> Date: Sat, 30 May 2009 20:55:21 -0700 X-Google-Sender-Auth: 648ec9cd2455da07 Message-ID: <3c1674c90905302055g542cfadarf201cc273639977d@mail.gmail.com> From: Kip Macy To: bf Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: attilio@freebsd.org, ohartman@mail.zedat.fu-berlin.de, freebsd-current@freebsd.org Subject: Re: signifanctly slowdown of FreeBSD 8.0-CURRENT/amd64 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 31 May 2009 03:55:22 -0000 > > I'm running the r193133 amd64 with a custom kernel and all debugging off > on an AMD Athlon64 3400+ single-core, and I haven't noticed any significa= nt > slowing, although I haven't been doing any systematic benchmarking. > > What would be the penalties of running an SMP -CURRENT kernel on > single-core hardware with no hyperthreading? Can anyone quantify the > typical added overhead? =A0Or, counterintuitively, would an SMP kernel > be better in some ways? > He is trying to diagnose if the problem was introduced by enabling adaptive spinning on sx locks. They're only enabled on SMP kernels. Cheers, Kip