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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D1DCDC433DB for ; Fri, 12 Mar 2021 15:10:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A993964FDC for ; Fri, 12 Mar 2021 15:10:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232213AbhCLPJ5 (ORCPT ); Fri, 12 Mar 2021 10:09:57 -0500 Received: from mga17.intel.com ([192.55.52.151]:22264 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231679AbhCLPJe (ORCPT ); Fri, 12 Mar 2021 10:09:34 -0500 IronPort-SDR: Ugc0D/jpEyCdLH0SNzjbwKmE/zGBJoCVNyYNxwZN8gpMJyf6INQyWFZFVsbyIJIVNhux7WCmUJ R1E6ZavPjffw== X-IronPort-AV: E=McAfee;i="6000,8403,9921"; a="168758279" X-IronPort-AV: E=Sophos;i="5.81,243,1610438400"; d="scan'208";a="168758279" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Mar 2021 07:09:34 -0800 IronPort-SDR: lTby2jTgpVlL6h7WA/5C/RF/rZaMGkanAH6q6nnlYdgYqT6pVCydQioMJ6RuyBT8NQAvWq1+jd 8SltHgf3aj8g== X-IronPort-AV: E=Sophos;i="5.81,243,1610438400"; d="scan'208";a="448644680" Received: from tassilo.jf.intel.com ([10.54.74.11]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Mar 2021 07:09:34 -0800 Date: Fri, 12 Mar 2021 07:09:33 -0800 From: Andi Kleen To: Namhyung Kim Cc: Arnaldo Carvalho de Melo , Jiri Olsa , Ingo Molnar , Peter Zijlstra , Mark Rutland , Alexander Shishkin , LKML , Stephane Eranian , Ian Rogers Subject: Re: [PATCH 0/3] perf tools: Minor improvements in event synthesis Message-ID: <20210312150933.GN203350@tassilo.jf.intel.com> References: <20201221070029.1451176-1-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201221070029.1451176-1-namhyung@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 21, 2020 at 04:00:26PM +0900, Namhyung Kim wrote: > Hello, > > This is to optimize the event synthesis during perf record. > > The first patch is to reduce memory usage when many threads are used. > The second is to avoid unncessary syscalls for kernel threads. And > the last one is to reduce the number of threads to iterate when new > threads are being created at the same time. > > Unfortunately there's no dramatic improvement here but I can see ~5% > gain in the 'perf bench internals synthesize' on a big machine. > (The numbers are not stable though) Looks all good to me. The VmPeak assumption might be slightly fragile, but I guess there's nothing better currently. Reviewed-by: Andi Kleen -Andi