From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753449AbeCTNjB (ORCPT ); Tue, 20 Mar 2018 09:39:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:48786 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753170AbeCTNjA (ORCPT ); Tue, 20 Mar 2018 09:39:00 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 642E021716 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=acme@kernel.org Date: Tue, 20 Mar 2018 10:38:51 -0300 From: Arnaldo Carvalho de Melo To: Jan-Oliver Kaiser Cc: Peter Zijlstra , Ingo Molnar , linux-kernel@vger.kernel.org, milian.wolff@kdab.com Subject: Re: `perf report` about 1000x(!) slower in linux 4.15 Message-ID: <20180320133851.GB3784@kernel.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Mar 20, 2018 at 12:57:29PM +0100, Jan-Oliver Kaiser escreveu: > After upgrading my system to linux 4.15 (from 4.14), `perf report` became > unusably slow. I estimate a decrease in performance by a factor of > 100x-1000x. Some 21M perf.data files take about 30 seconds in the > "Processing events" step. `git bisect` points to > commit d8a88dd243a170a226aba33e7c53704db2f82aa6 (HEAD, refs/bisect/bad) > Author: Milian Wolff > perf util: Enable handling of inlined frames by default > The slowdown can be worked around with `--no-inline`. If the slowdown is > expected, I would suggest reverting the default setting here or maybe > printing a warning if a lot of time is spent on this feature. > Do you need any additional information about my system or the recorded data > I am looking at? Can you try with the latest perf tool? [acme@jouet perf]$ make perf-tarxz-src-pkg ; ls -la perf-4* TAR PERF_VERSION = 4.16.rc6.gecd380 -rw-rw-r--. 1 acme acme 1323568 Mar 20 10:30 perf-4.16.0-rc6.tar.xz [acme@jouet perf]$ With a recently checked out kernel sources, or, as a convenience, I'm pushing this to: http://vger.kernel.org/~acme/perf/perf-4.16.0-rc6.tar.xz You just expand it and then: [acme@jouet tmp]$ tar xf perf-4.16.0-rc6.tar.xz [acme@jouet tmp]$ cd perf-4.16.0-rc6/ [acme@jouet perf-4.16.0-rc6]$ make -C tools/perf install-bin And check if the problem is present there as well. If it is, please tell us what is your distro, the output of: perf report --header-only Thanks, - Arnaldo