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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 4BDCAC3B188 for ; Wed, 12 Feb 2020 11:50:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20ACB20675 for ; Wed, 12 Feb 2020 11:50:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="f+xis38U" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728328AbgBLLu6 (ORCPT ); Wed, 12 Feb 2020 06:50:58 -0500 Received: from mail-pf1-f172.google.com ([209.85.210.172]:41212 "EHLO mail-pf1-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726775AbgBLLu6 (ORCPT ); Wed, 12 Feb 2020 06:50:58 -0500 Received: by mail-pf1-f172.google.com with SMTP id j9so1122930pfa.8 for ; Wed, 12 Feb 2020 03:50:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=SNJguF6fXZBD64srEgTMtsMKvmaYnTcmUx5yaV0STFc=; b=f+xis38Uz6BT0DmvvXp+IvwfnKh6g1L/jH0cqofQHcDHWBACS390J+tZaAi6huv+Rh QJxI2p15/yVGD6TYb28+InPftcXlfQ3HDofnU3/7EIi3hGVG2rwTINrxiLyFzUDZ3EEr VK1uvyedHpX3RgVhzHK+tyo2OLqlRTF1/YQn0k+0khY93GzClfj38QEQAg83FcPrf+gA jNIaT8xLFdv41K2N7FdYXBtP7zisW/09fQH6iJZG9tC4sPXz9JQ0V/+GIhIpfobz6Mk3 zsNArCtKsDxKF7cXNh3ic6RdrXF/PZtTuYU455vFNrb430A4sv+WMdaGtAuE4p6fm+1+ qs1w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=SNJguF6fXZBD64srEgTMtsMKvmaYnTcmUx5yaV0STFc=; b=UGcRkqAXh6dXH1/xAzoAeH57bL9615f4NhKdP982nziVHGc+NIg3uR01LEsqAbdwoM 2sowqdV2HVpj07lLT53qHFf2achddZ8dUpRKKTpXrRigSQAMey6RUemBPcAKiMpEK5eS O1VbqgRSSX4/L6bfbIYc5+rv8R6GBvTJiYJ6JEF8XUJZIXJaI/zfc8mwVGAkt5Zw1tUc SUecemYde1cdOTqPtby+eLFr+k3x96qyqMl/N5w7xS99WddwGCV3abQ/GYCEzeHWr76J uhsSql4aki8ENt5nQDJr88Kiokdwzy4oBJGRAmxnoT4a4svtEiG1rwtAeN8Haidr1eza OtLg== X-Gm-Message-State: APjAAAV7GRq8Tp4yQzqR6VgY8qbgEosdJkQ3EDbeVs2Wt/H8ctDy1wCN rPgR7Tk1sIGpcvO1gRT5DC3Sn4hCpc8= X-Google-Smtp-Source: APXvYqziM45BHS5NCatso9nOdPDZJApXtrAgVmVANASFFMD2orkwO0oZECtWpUO5UT3u6uxcs6d5Rw== X-Received: by 2002:aa7:9a0b:: with SMTP id w11mr11402186pfj.4.1581508257625; Wed, 12 Feb 2020 03:50:57 -0800 (PST) Received: from localhost ([122.167.210.63]) by smtp.gmail.com with ESMTPSA id y16sm570249pfn.177.2020.02.12.03.50.56 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 12 Feb 2020 03:50:56 -0800 (PST) Date: Wed, 12 Feb 2020 17:20:54 +0530 From: Viresh Kumar To: Andy Tang Cc: "rjw@rjwysocki.net" , "linux-pm@vger.kernel.org" Subject: Re: [EXT] Re: Ask for help about cpufreq issue Message-ID: <20200212115054.eouh7e42uqlcweo3@vireshk-i7> References: <20200207052321.povhuxrlm25ueoak@vireshk-i7> <20200207070544.geurecsy4i22xpzl@vireshk-i7> <20200211055315.qlqrxiqf72u36ijl@vireshk-i7> <20200211063439.aqc4h6np3wjpsg2j@vireshk-i7> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716-391-311a52 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 12-02-20, 10:11, Andy Tang wrote: > Hi Viresh, > > I have another cpufreq issue on our lx2160a platform which has 16 cores and 8 clusters. > > Cpufreq works well for ondemand, performance governor. > But for conservative governor, even though cpu usage is almost zero, but some cpus are not > work on the lowest frequency sometimes. It keeps bouncing from the lowest frequency > to the other higher frequencies. > The defaut values are used for the tunable for conservative governor. > In summary, why cpu doesn't work at the lowest frequency even the cpu load is almost zero? > > root@lx2160ardb:/sys/devices/system/cpu# cat cpufreq/conservative/ > down_threshold freq_step ignore_nice_load sampling_down_factor sampling_rate up_threshold > root@lx2160ardb:/sys/devices/system/cpu# cat cpufreq/conservative/* > 20 Try increasing down_threshold to a value of 50 (i.e. we reduce frequency if the load is below 50%) and see if it makes a difference. I believe something is running on the CPU, that you are unaware of. Try doing tracing to see what's going on all CPUs. -- viresh