From owner-freebsd-current@FreeBSD.ORG Fri Jul 10 14:39:19 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 6CABF106568C for ; Fri, 10 Jul 2009 14:39:19 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-yx0-f181.google.com (mail-yx0-f181.google.com [209.85.210.181]) by mx1.freebsd.org (Postfix) with ESMTP id 0A2FD8FC24 for ; Fri, 10 Jul 2009 14:39:18 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: by yxe11 with SMTP id 11so1553339yxe.3 for ; Fri, 10 Jul 2009 07:39:18 -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=srr0sqRu7o9hckQW2xZn7QaKVdc/+uWslNFbgKuUlsg=; b=mKYL+90oaYBPKsenB3usQCYoWkV3Zr2+CdYULu2skcSE2qRN2XKiv7kDqShtWNG9ct sGn9ELYstAdGINWzxjuMDp8pSCfSKQS/FdUcQomNI5hxM4/CKHW4956IpdbthOCSBTlN OiaFNYdvkJhhK5k5Dy2/hNKRFWB/wjMqL6YvA= 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=EOqbkVW23mNzUzGFjh4AOrx8iedgYmcPGm9Fm8rZLC/zbmtRv4J8udJcXkzp1Sj2I7 fE/LAG6qtpHlQNLizkB62wMrwq30bMc/8eXfSOhMc5jXBei4pFgRTvuf3PddefcgqnWf tA82kYj6Fkt00R6n1cwGGlrtw4AcbDSGIhOPA= MIME-Version: 1.0 Sender: adrian.chadd@gmail.com Received: by 10.100.13.14 with SMTP id 14mr2792640anm.51.1247236758482; Fri, 10 Jul 2009 07:39:18 -0700 (PDT) In-Reply-To: <4A5733A3.20409@freebsd.org> References: <4A562960.3010801@freebsd.org> <4A5733A3.20409@freebsd.org> Date: Fri, 10 Jul 2009 22:39:18 +0800 X-Google-Sender-Auth: 1d0406cc236a3d8d Message-ID: From: Adrian Chadd To: Andriy Gapon Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Andrew Brampton , freebsd-current@freebsd.org Subject: Re: dtrace users opinion solicited (timestamps) 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: Fri, 10 Jul 2009 14:39:19 -0000 2009/7/10 Andriy Gapon : >> Another problem with this is that on a multicore machine each core may >> have different TSC values. Has anyone thought how to address this >> issue? Could we calculate the offset of each core from core0, and then >> ensure the offset is applied to the tsc value when it is needed? > > Yes. The actual code accounts for inter-CPU/core TSC skew. Pardon the stupid question, but how does Solaris deal with this? Adrian