From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756981AbXEJPXJ (ORCPT ); Thu, 10 May 2007 11:23:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753215AbXEJPW6 (ORCPT ); Thu, 10 May 2007 11:22:58 -0400 Received: from x35.xmailserver.org ([64.71.152.41]:3737 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753043AbXEJPW5 (ORCPT ); Thu, 10 May 2007 11:22:57 -0400 X-AuthUser: davidel@xmailserver.org Date: Thu, 10 May 2007 08:22:51 -0700 (PDT) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Andi Kleen cc: Linux Kernel Mailing List , William Lee Irwin III Subject: Re: [patch 1/4] KMON - kmon device/instrumentation ... In-Reply-To: Message-ID: References: X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 10 May 2007, Andi Kleen wrote: > Davide Libenzi writes: > > > This patch serie introduces a way to log high frequency/volume data > > out of the kernel. Logging scheduler operations for example, with > > loads that generate tenths of thousands of context switches per second > > (possibly from multiple CPUs), can overload the kernel printk. Also, > > logging in binary form helps in reducing the size of the logged data > > that is tranfered from kernel to userspace. The kmon logger uses per > > CPU buffers (rings) that are flushed at a given frequency to all the > > instances of the kmon devices. > > Sounds like you reinvented relayfs? (and ktrace before that) I simply didn't know about relayfs ;) Randy told me when I posted those, that BTW were never intended for merging. The buffering method used is more similar to oprofile though. - Davide