Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752748AbWKBIwu (ORCPT ); Thu, 2 Nov 2006 03:52:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752750AbWKBIwu (ORCPT ); Thu, 2 Nov 2006 03:52:50 -0500 Received: from nz-out-0102.google.com ([64.233.162.199]:17358 "EHLO nz-out-0102.google.com") by vger.kernel.org with ESMTP id S1752748AbWKBIwt (ORCPT ); Thu, 2 Nov 2006 03:52:49 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=Oa89nfP5WbAZ/5c2rRxGXBncmxrTd3tqX+n8+8c50QfnK1Vb1Pky7WYypgWtHNep1ILEy5Xw8GU8u3SdL6TeS7vXqWYTarq5xG4/8yvgXb1Enrz4ZENOkNNWUgToUS45C7Ifko9LTdPfDlbH0eh18Wy6saHkqBDF5AanmyimPXk= Message-ID: Date: Thu, 2 Nov 2006 16:52:48 +0800 From: "FENG ZHOU" To: linux-kernel@vger.kernel.org Subject: How to optimize system time for such case? In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1021 Lines: 20 Hello, all I am optimizing a compiler and I believe there is a bug in such compile. Currently, I have a test case, which is a scientific application, has a lot of system time. This is weird, because this case does not have many system calls. Meanwhile, compiled at another option, I found all the "system time" are gone! So, I assume there is some problem in the first one (though both binary produce correct result). I used some performance tuning tool and found the hottest address for CPU privilege level change event is: 0xa000000100001a70. This address is not in code or data segment. Now, I am kinda stuck here. My question is: how to find what this address is? Or find out what is the cause of the "system time"? Thanks in advance. PS: the platform is Itanium 2. -Feng - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/