From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: What does several of perf configurations (alias, help, call-graph) mean ? Date: Thu, 5 Feb 2015 15:06:32 +0100 Message-ID: <20150205140632.GB16369@kernel.org> References: <54D3242A.8050606@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail.kernel.org ([198.145.29.136]:42107 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753111AbbBEOGV (ORCPT ); Thu, 5 Feb 2015 09:06:21 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 34EA220274 for ; Thu, 5 Feb 2015 14:06:20 +0000 (UTC) Received: from zoo.ghostprotocols.net (ip-94-112-29-173.net.upcbroadband.cz [94.112.29.173]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 324642026F for ; Thu, 5 Feb 2015 14:06:19 +0000 (UTC) Content-Disposition: inline In-Reply-To: <54D3242A.8050606@gmail.com> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: taeung Cc: linux-perf-users@vger.kernel.org Em Thu, Feb 05, 2015 at 05:04:58PM +0900, taeung escreveu: > > Hi, every one. :-) > > I'm tring to make things about perf configuration neat and tidy. > Three questions have arisen doing it. > > 1. alias [ util/alias.c : alias_lookup_cb(), util/help.c : > perf_unknown_cmd_config() ] > > What kind of alias keys are there ? I'm unaware of any, this came from the git sources where this concept of 'alias' must be used. > 2. help [ builtin-help.c : perf_help_config() ] > > 'autocorrect' can have a value of integer type. > What does the value mean ? Also comes from git, where it does things like: [acme@zoo linux]$ git ckone git: 'ckone' is not a git command. See 'git --help'. Did you mean this? clone But perf doesn't and instead: [acme@zoo linux]$ perf repjort perf: 'repjort' is not a perf-command. See 'perf --help'. [acme@zoo linux]$ I guess this is what 'autocorrect' stands for, unsure tho. > 3. call-graph [ util/callchain.c : perf_callchain_config(), > parse_callchain_record_opt() ] > > record-mode can be 'Framepointer style' or 'Dwarf style'. > Why does 'Dwarf style' accompany dump-size ? For these things I think you should try to use 'git blame', figure out when this was introduced and get the documentation bits from there... did it, was a bit more complicated as there was code move in these areas but this is the cset that introduced this feature: 26d330226b9cf6208daae9b0b3697980c8fb51d8 commit 26d330226b9cf6208daae9b0b3697980c8fb51d8 Author: Jiri Olsa Date: Tue Aug 7 15:20:47 2012 +0200 perf tools: Support for DWARF mode callchain This patch enables perf to use the DWARF unwind code. It extends the perf record '-g' option with following arguments: 'fp' - provides framepointer based user stack backtrace 'dwarf[,size]' - provides DWARF (libunwind) based user stack backtrace. The size specifies the size of the user stack dump. If omitted it is 8192 by default. If libunwind is found during the perf build, then the 'dwarf' argument becomes available for record command. The 'fp' stays as default option in any case. Examples: (perf compiled with libunwind) perf record -g dwarf ls - provides dwarf unwind with 8192 as stack dump size perf record -g dwarf,4096 ls - provides dwarf unwind with 4096 as stack dump size perf record -g -- ls perf record -g fp ls - provides frame pointer unwind Signed-off-by: Jiri Olsa Original-patch-by: Frederic Weisbecker > 'threshold' can have a value of double type > and the value can be entered into callchain_param.min_percent. > What does 'threshold' mean ? Ditto: commit 805d127d62472f17c7d79baa001a7651afe2fa47 Author: Frederic Weisbecker Date: Sun Jul 5 07:39:21 2009 +0200 perf report: Add "Fractal" mode output - support callchains with relative overhead rate But especifically on the function you mention, the meaning looks obvious, its the minimal percentage that that entry in the callchain must have to appear on the output. - Arnaldo