From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from wp530.webpack.hosteurope.de (wp530.webpack.hosteurope.de [80.237.130.52]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B99BE2C82 for ; Mon, 1 Nov 2021 12:54:23 +0000 (UTC) Received: from ip4d173d4a.dynamic.kabel-deutschland.de ([77.23.61.74] helo=[192.168.66.200]); authenticated by wp530.webpack.hosteurope.de running ExIM with esmtpsa (TLS1.3:ECDHE_RSA_AES_128_GCM_SHA256:128) id 1mhWpR-00024G-VB; Mon, 01 Nov 2021 13:54:22 +0100 Message-ID: Date: Mon, 1 Nov 2021 13:54:21 +0100 Precedence: bulk X-Mailing-List: regressions@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.2.0 Subject: Re: Thorsten is tracking regression again and could need a little help (was: Re: Linux 5.15) Content-Language: en-BS To: Idzibear Cc: linux-kernel@vger.kernel.org, regressions@lists.linux.dev, torvalds@linux-foundation.org References: From: Thorsten Leemhuis In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-bounce-key: webpack.hosteurope.de;regressions@leemhuis.info;1635771263;8841dc75; X-HE-SMSGID: 1mhWpR-00024G-VB On 01.11.21 12:46, Idzibear wrote: > https://www.reddit.com/r/linux/comments/qjyxso/the_515_kernel_has_been_released/hitiykt/ > > I just noticed something strange. I'm experimenting with some repurposed > Desktop-PC to make it maybe into a homelab server. > > I ran Kernel 5.14.10, and I had an idle usage of 19-22 watts. Updated to > 5.15 and it went to 27-29 watts. Went back to 5.14.10 and it went down > to 19-22 watts again. WTF? thx for the report, yeah, sound like a regression. With that much of a difference I'd suspect it's something that can consume a lot of power if not sleeping properly, for example the CPU or the GPU. But that's just a shot in the dark and it's hard to help here with debugging from a distance (especially without a list of hardware components). With a bit of luck tools like powertop might be able to debug this (check if the CPU is sleeping well). But a 'git bisect', like already suggested Gregkh, would be really the best to find the change that's causing this. Ciao, Thorsten #regzbot ^introduced: v5.14..v5.15 #regzbot title: idle power increased from ~20 to ~28 watts