From owner-freebsd-performance@FreeBSD.ORG Fri Dec 14 04:07:04 2007 Return-Path: Delivered-To: freebsd-performance@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 73A6C16A417 for ; Fri, 14 Dec 2007 04:07:04 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.178]) by mx1.freebsd.org (Postfix) with ESMTP id 542D913C45B for ; Fri, 14 Dec 2007 04:07:04 +0000 (UTC) (envelope-from kip.macy@gmail.com) Received: by wa-out-1112.google.com with SMTP id k17so1563702waf.3 for ; Thu, 13 Dec 2007 20:07:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; bh=2eQOHn/AKUg1+DWOoeB+LcuXXCfksU1D9TiwfEcAOHk=; b=VbFAjmGYblYREd1fS2dwfNoNAG1BYMv+jAIyx70NIlqtMUqItGh7zcJqGarDgmFEw4CuHdwTZL1+TXSGENjVUCcel65UZsu+8kDEi5RrVDAvjgqYWaMCL6r1RT84dlZT+QGvbEpkgX0wAwLshnFyflOwgy2YfCF7D/EoxsEP/6g= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=E8o6DeQ2VlkCwEIg0S8KDuC37WsDq+/DmO/cGa8kFfsEvPaUMPIEp3qul39gQgR/i2UnUTokHFUaij7VYEC0ln63etneVHA2Hnakw9EwZ4oNk0qDr13Xv4fJS3rUbA8cDtu07fi9Q9JtJ8RCqyrM6PG4PJZKp+k8c67f/giJn30= Received: by 10.114.93.17 with SMTP id q17mr3173915wab.70.1197603709968; Thu, 13 Dec 2007 19:41:49 -0800 (PST) Received: by 10.114.255.11 with HTTP; Thu, 13 Dec 2007 19:41:49 -0800 (PST) Message-ID: Date: Thu, 13 Dec 2007 19:41:49 -0800 From: "Kip Macy" To: "Shantanu Ghosh" In-Reply-To: <963530.77689.qm@web54505.mail.re2.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <963530.77689.qm@web54505.mail.re2.yahoo.com> Cc: freebsd-performance@freebsd.org Subject: Re: freebsd vs linux: performance problem X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 14 Dec 2007 04:07:04 -0000 On Dec 13, 2007 4:07 AM, Shantanu Ghosh wrote: > Hi, > > I am running FreeBSD 7.0 Beta1 and Linux FC6 on two identical pieces of > hardware - Dell poweredge with intel core2 duo. Each system has 4 CPUs. > > Now, in simple memory access operations, I see the freebsd system being > noticably slower than the linux system. A simple C program that copies > from one memory buffer to another, when executed in a loop executes > between 10-30% slower on freebsd, as compared to linux. The assembly > code of the program used for testing is identical in both the cases. > > One observation is that freebsd system performance decreases as the > size of the buffer increases. If the buffer is under 1k, both the > sytems give the same performance. freebsd performance is about 10% > slower if the buffer size is around 4k, and about 30% slower if the > buffer is around 1Mb. A benchmark like sysbench memory read operation > performs miserably on the freebsd system, compared to linux. > > As far as I can see, the BIOS settings are identical on both the > machines. Any idea what could be going on? Are you running with ULE or 4BSD? Have you checked that the BIOS cache settings are identical? -Kip