From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20803 invoked by alias); 7 Apr 2006 08:43:14 -0000 Received: (qmail 20795 invoked by uid 22791); 7 Apr 2006 08:43:13 -0000 X-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,SPF_PASS,SUBJ_HAS_UNIQ_ID X-Spam-Check-By: sourceware.org Received: from mtagate2.uk.ibm.com (HELO mtagate2.uk.ibm.com) (195.212.29.135) by sourceware.org (qpsmtpd/0.31) with ESMTP; Fri, 07 Apr 2006 08:43:09 +0000 Received: from d06nrmr1407.portsmouth.uk.ibm.com (d06nrmr1407.portsmouth.uk.ibm.com [9.149.38.185]) by mtagate2.uk.ibm.com (8.13.6/8.13.6) with ESMTP id k378h64V241254 for ; Fri, 7 Apr 2006 08:43:06 GMT Received: from d06av02.portsmouth.uk.ibm.com (d06av02.portsmouth.uk.ibm.com [9.149.37.228]) by d06nrmr1407.portsmouth.uk.ibm.com (8.12.10/NCO/VER6.8) with ESMTP id k378hegu058866 for ; Fri, 7 Apr 2006 09:43:40 +0100 Received: from d06av02.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av02.portsmouth.uk.ibm.com (8.12.11/8.13.3) with ESMTP id k378h5Ji006606 for ; Fri, 7 Apr 2006 09:43:06 +0100 Received: from d06ml065.portsmouth.uk.ibm.com (d06ml065.portsmouth.uk.ibm.com [9.149.38.138]) by d06av02.portsmouth.uk.ibm.com (8.12.11/8.12.11) with ESMTP id k378h501006597; Fri, 7 Apr 2006 09:43:05 +0100 In-Reply-To: <20060407082517.GA7546@in.ibm.com> Subject: Re: [...] kprobes [minutes] portion 20060406 Sensitivity: To: prasanna@in.ibm.com Cc: "Frank Ch. Eigler" , Hien Q Nguyen , systemtap@sources.redhat.com X-Mailer: Lotus Notes Release 6.5.1IBM February 19, 2004 Message-ID: From: Richard J Moore Date: Fri, 07 Apr 2006 08:43:00 -0000 X-MIMETrack: Serialize by Router on D06ML065/06/M/IBM(Release 6.53HF247 | January 6, 2005) at 07/04/2006 09:43:39 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII X-IsSubscribed: yes Mailing-List: contact systemtap-help@sourceware.org; run by ezmlm Precedence: bulk List-Subscribe: List-Post: List-Help: , Sender: systemtap-owner@sourceware.org X-SW-Source: 2006-q2/txt/msg00064.txt.bz2 systemtap-owner@sourceware.org wrote on 07/04/2006 09:25:17: > > On Thu, Apr 06, 2006 at 05:28:38PM -0400, Frank Ch. Eigler wrote: > > Hi - > > > > On Thu, Apr 06, 2006 at 02:14:46PM -0700, Hien Q Nguyen wrote: > > > User space probe > > > Prasanna had prototype that execute the handler in the user space [...] > > > > Beyond merely dispatching, it is important to consider what such a > > handler can do. Would it still be useful if it cannot call into the > > kernel-side runtime, if it cannot share variables with kernel-space > > probes? > > No. The purpose of prototype was to see how it can be implemented. > To my opinion having handler run in user-space does not suit well for > system-wide tracing. But that might be one of the alternative approaches > to per-process tracing, since ptrace is found to have more performance > related problems. > > Agreed, but don't let the creation of per-process probe handlers detract from the argument for a system-wide capabiltiy; that's the real battle-ground. Richard > Thanks > Prasanna > -- > Thanks & Regards > Prasanna S Panchamukhi > Linux Technology Center > India Software Labs, IBM Bangalore > Email: prasanna@in.ibm.com > Ph: 91-80-51776329