From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757582AbeAICCg (ORCPT + 1 other); Mon, 8 Jan 2018 21:02:36 -0500 Received: from mga02.intel.com ([134.134.136.20]:6731 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756960AbeAICCe (ORCPT ); Mon, 8 Jan 2018 21:02:34 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,333,1511856000"; d="scan'208";a="8548158" Subject: Re: [PATCH v7 5/6] perf report: support time percent and multiple time ranges To: Arnaldo Carvalho de Melo Cc: jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com, Linux-kernel@vger.kernel.org, ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com References: <1512738826-2628-1-git-send-email-yao.jin@linux.intel.com> <1512738826-2628-6-git-send-email-yao.jin@linux.intel.com> <20180108145336.GF25476@kernel.org> <20180108150235.GG25476@kernel.org> <20180108150451.GH25476@kernel.org> From: "Jin, Yao" Message-ID: <63f2abf4-9a3e-a655-dbb7-301ad42a78f3@linux.intel.com> Date: Tue, 9 Jan 2018 10:02:32 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.5.2 MIME-Version: 1.0 In-Reply-To: <20180108150451.GH25476@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On 1/8/2018 11:04 PM, Arnaldo Carvalho de Melo wrote: > One more thing to consider: > > When you use: > > perf report --time 10%/1 > > it will do what is asked but there is no indication of what percentage > ranges are in place, it would be nice to have this in the first line in > the TUI, right after this: > > Samples: 128 of event 'cycles:ppp', Event count (approx.): 21386169 (10%/1) > > - Arnaldo > Hi Arnaldo, Thanks for merging this feature and thanks so much for providing comments for how to improve this feature in next step. Please let me summarize what the follow-up patch needs to do: 1. Improve the error message, something like: "HINT: use 'perf record --foobar' to record the first/last sample timestamps in the perf.data file header or enable build-id processing." 2. Currently it uses magic number 10 to limit the number of time slices. But it's not good. The best thing would be to have no such limitations, i.e. to lift this limitation from the code and docs. 3. 'perf report --time 10%' should be equivalent to 'perf report --time 10%/1'. Or at least say something like: "percent slices need an index to specify which one is wanted" when you notice a % in the --time string, etc. 4. Add an indication of what percentage ranges are being used. For example, Samples: 128 of event 'cycles:ppp', Event count (approx.): 21386169 (10%/1) I will develop a follow-up patchset to improve this feature. Thanks Jin Yao