From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 27CFBECDFD0 for ; Fri, 14 Sep 2018 11:15:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B47E020881 for ; Fri, 14 Sep 2018 11:15:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="cceObBz0" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B47E020881 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727847AbeINQ3k (ORCPT ); Fri, 14 Sep 2018 12:29:40 -0400 Received: from merlin.infradead.org ([205.233.59.134]:39898 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726872AbeINQ3k (ORCPT ); Fri, 14 Sep 2018 12:29:40 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=EDqV7I68fZIzt+sf0o3AMGjwVBQHajms74yT5v7MaAM=; b=cceObBz0hdtGSVG4vsztaXk52 mFp8udfc1VRMj9UIvUOfN29zPSJWdmDODAGAt+4aLMLao1tKbrLzaN0AdSg4TGPHVqJGlIpwx5/ci fP0HMSVUc89lvpm0HIHJnt5SDA6FDPJ583XKXpUw4YCVVOLZ9Q5THm2fEk0C1HKtB0cpkTYNcXGDj zaLZRiV5JzTPIwXOFVhdTULFbiCrsqKWLab0vCZaBiQ3l55BMIiUZY0gtL7bJtGH50C9tEbknUbij o0E8V6GT+NK1quy3Lvm5WJ2nbeQdvEy4HhuS6r6DTJQaOMrrN6puVlYqEEUvDOT0BjwSsXM8s41C3 +kun5aSnA==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=hirez.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1g0m4P-00028m-KB; Fri, 14 Sep 2018 11:15:29 +0000 Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 68E8D202C1A09; Fri, 14 Sep 2018 13:15:28 +0200 (CEST) Date: Fri, 14 Sep 2018 13:15:28 +0200 From: Peter Zijlstra To: Ingo Molnar Cc: Jiri Olsa , Namhyung Kim , Alexey Budankov , Jiri Olsa , Arnaldo Carvalho de Melo , lkml , Alexander Shishkin , Andi Kleen , kernel-team@lge.com Subject: Re: [RFCv2 00/48] perf tools: Add threads to record command Message-ID: <20180914111528.GH24124@hirez.programming.kicks-ass.net> References: <20180913125450.21342-1-jolsa@kernel.org> <20180914022910.GA15146@sejong> <20180914082307.GF24224@krava> <20180914094022.GB96351@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180914094022.GB96351@gmail.com> User-Agent: Mutt/1.10.0 (2018-05-17) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 14, 2018 at 11:40:22AM +0200, Ingo Molnar wrote: > In fact keeping the files separate has scalability advantages for 'perf report' and similar > parsing tools: they could read all the streams in a per-CPU fashion already, from the very > beginning. Also writing to different files from different CPUs is good for record, less contention on the inode state (which include pagecache).