Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 30 Oct 2002 22:04:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 30 Oct 2002 22:04:04 -0500 Received: from nameservices.net ([208.234.25.16]:6064 "EHLO opersys.com") by vger.kernel.org with ESMTP id ; Wed, 30 Oct 2002 22:04:03 -0500 Message-ID: <3DC0A01B.15B8B535@opersys.com> Date: Wed, 30 Oct 2002 22:14:35 -0500 From: Karim Yaghmour Reply-To: karim@opersys.com Organization: Opersys inc. X-Mailer: Mozilla 4.79 [en] (X11; U; Linux 2.4.19 i686) X-Accept-Language: en MIME-Version: 1.0 To: Linus Torvalds CC: Rusty Russell , linux-kernel@vger.kernel.org, LTT-Dev Subject: Re: What's left over. References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1668 Lines: 41 Linus Torvalds wrote: > > Linux Trace Toolkit (LTT) > > I don't know what this buys us. How about being able to: - Debug synchronization problems among processes (there is no other tool to do this, not gdb, not strace, not printf, ...) - Measure exact time spent wainting for kernel and which other processes a process had to wait for. - Measure exact time it takes for an interrupt's effects to propagate throughout the entire system. - Understand the exact behavior the system has to input. (what is the exact sequence of processes that run when I press a key). - Identify sporadic problems in very saturated systems. (thousands of servers and one of them is doing weird stuff). - etc. Providing system tracing is a necessity for any sort of complex application development and system monitoring. Some people simply can't use Linux without this sort of tool and I am at pains to explain to them why they actually have to patch their kernel to be able to debug their inter-process synchronization problems. Users don't have to patch their kernel to use gdb and I don't see why they should need to patch their kernel to understand how their various processes interact with the kernel and vice-versa. Karim =================================================== Karim Yaghmour karim@opersys.com Embedded and Real-Time Linux Expert =================================================== - 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/