From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761267AbXEJM0s (ORCPT ); Thu, 10 May 2007 08:26:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755024AbXEJM0m (ORCPT ); Thu, 10 May 2007 08:26:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:49824 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754794AbXEJM0l (ORCPT ); Thu, 10 May 2007 08:26:41 -0400 To: Davide Libenzi Cc: Linux Kernel Mailing List , William Lee Irwin III Subject: Re: [patch 1/4] KMON - kmon device/instrumentation ... References: From: Andi Kleen Date: 10 May 2007 15:23:50 +0200 In-Reply-To: Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 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 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) -Andi