From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f42.google.com (mail-ej1-f42.google.com [209.85.218.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F7E24F8BE for ; Wed, 10 Jan 2024 22:41:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linuxfoundation.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="WIwmPBaN" Received: by mail-ej1-f42.google.com with SMTP id a640c23a62f3a-a28bf46ea11so824411166b.1 for ; Wed, 10 Jan 2024 14:41:36 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; t=1704926494; x=1705531294; darn=vger.kernel.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=k35Q5QIp5MyCO5VamMpz/sosd3XUE8jfAcVkkJ5lw8w=; b=WIwmPBaN+fnxhCnsUZpFRiiAwkdKy40erGNezc9/qpWeTaUS7a8SXq2I9uQw2PaFkk PUSvzS3Dt/MzEr979OxwuibZwYo3C2xBhHl8sGIBIU92xyYtwjw8y3Ns6jqlAKzVnWEd 1JPkxG0oxotNg4uvCk+D5ek2s/VMyKE4emPh4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704926494; x=1705531294; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=k35Q5QIp5MyCO5VamMpz/sosd3XUE8jfAcVkkJ5lw8w=; b=ZtEU0IrlX93DvGIQkaE17yXb3ZhvZAxs5Cz2kgTRZvGg8GYdWPmxZ4ccC/+rrSEYcN V+osPqO9BoqSnJ+EfQVyGDILE1DaGeVMrjFCFkLrtiivBx/Yky7hwpyfs4+AyfmFswbp LI+/8PPiFLUUOyCwIESCxDR7Nzf2MH4qy3wxi7PEWjPaPJBqtc3t0lTaXPLhnl0YlB7T wSyYxPGTzI7fEyQ1YwSMeooSueCrggg9FsgdcEWUKkV/Jr7R8nKHT126Zt2UsGTcT+7p 0rTKx8Yo7f96wnPekjCd0nqA1akOJ0MK7eHumYFv/XrLJD3vGChh1fS16iVqYV29J7eg sYSw== X-Gm-Message-State: AOJu0YxQIUMRnJuCCLxAW1WcP0dBRyCCZEfBWy5bWsZzoayzyqAS7R1Q kWdNwmIW79wUlWGOr2FsfinM6N9u+xHUM+dKE5qIQ6UMHv/w2vbq X-Google-Smtp-Source: AGHT+IG9VSi409USpyKYbUV0j0ICoFJvK87emHDKRmy7wNFQLKBCwJ0em+lf2BM1aZpfyr86R7z49w== X-Received: by 2002:a17:906:a142:b0:a27:d309:b6b8 with SMTP id bu2-20020a170906a14200b00a27d309b6b8mr171973ejb.35.1704926494517; Wed, 10 Jan 2024 14:41:34 -0800 (PST) Received: from mail-ej1-f49.google.com (mail-ej1-f49.google.com. [209.85.218.49]) by smtp.gmail.com with ESMTPSA id le15-20020a170907170f00b00a2a0212cfe1sm2485362ejc.50.2024.01.10.14.41.33 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Jan 2024 14:41:34 -0800 (PST) Received: by mail-ej1-f49.google.com with SMTP id a640c23a62f3a-a28da6285c1so841066166b.0 for ; Wed, 10 Jan 2024 14:41:33 -0800 (PST) X-Received: by 2002:a17:906:b115:b0:a28:c04e:315b with SMTP id u21-20020a170906b11500b00a28c04e315bmr174538ejy.13.1704926493632; Wed, 10 Jan 2024 14:41:33 -0800 (PST) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: In-Reply-To: From: Linus Torvalds Date: Wed, 10 Jan 2024 14:41:16 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [GIT PULL] Scheduler changes for v6.8 To: Ingo Molnar , Vincent Guittot Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , Juri Lelli , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider Content-Type: text/plain; charset="UTF-8" On Wed, 10 Jan 2024 at 14:19, Linus Torvalds wrote: > > Just a note that I'm currently bisecting into this merge for a > horrendous performance regression. > > It makes my empty kernel build go from 22 seconds to 44 seconds, and > makes a full kernel build enormously slower too. > > I haven't finished the bisection, but it's now inside *just* this > pull, so I can already tell that I'm going to revert something in > here, because this has been making my merge window miserable. It's one of these two: f12560779f9d sched/cpufreq: Rework iowait boost 9c0b4bb7f630 sched/cpufreq: Rework schedutil governor performance estimation one more boot to go, then I'll try to revert whichever causes my machine to perform horribly much worse. Linus