From nobody Wed Feb 5 19:10:54 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 64C841DE4DC for ; Thu, 16 Jan 2025 12:46:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737031606; cv=none; b=VAOuEvR7aAXOjERp+j0tirPgrFNLTk+jyCoZXWg/cTyAEOQb86Xk+eJZ9Fxusw7rVaRYvz3UFiUEjnsOLvJPlaGeY4gZ7toq2er/GMoBx0tbuxHS1cdph6gW38iIlGnbIN0xz8khJ4jdkvhk4AwnK2klj7Y+hfeYcf6Ap9x84Rk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737031606; c=relaxed/simple; bh=gg387Pqxlm7HewJ3mPc+6XvzPEVSna7KZWXoaPpM7Yk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-type; b=qe8VX2rGmQY7bvLViNTBV12ugcjzUiswsyqrxc9quORgRtrw6sYpPItVk/nCMFqXv9LjTACRMpEKU6BmY5jMvL5LGoCemSNLJBJuLoDTVhUoSTNypjaWuYvM1xn3WyhEHQUzMGjxxWloxmhd5aEbs1q+1sJh1sUgktHkDncpDbo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=FwGZeNYF; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FwGZeNYF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1737031603; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=gPpbF5SoiqNaVSk//w8VuOWK6IzTz0Jex5iwN1xlcH8=; b=FwGZeNYFpG2gwcJh8QpDyCcZc8aPjiNYbWfXBh7A164SdeQAhmjTIuefjSRWCMvEDapGq3 o60Oi87d9BsCgyvdU53Bv+pGkZhMe0HRqOdBwC8UkoDtbJMyL1oRRx/W3Y/OenPwrspSKo nTxlEPGSjo+0dQJ6Ci3BvWM0xzZuacU= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-126-sKfSB8tFMRKNWgo7GaRyjg-1; Thu, 16 Jan 2025 07:46:41 -0500 X-MC-Unique: sKfSB8tFMRKNWgo7GaRyjg-1 X-Mimecast-MFC-AGG-ID: sKfSB8tFMRKNWgo7GaRyjg Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 4775E1956066; Thu, 16 Jan 2025 12:46:40 +0000 (UTC) Received: from isengard.. (vm-10-0-109-147.hosted.upshift.rdu2.redhat.com [10.0.109.147]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 87D7C1956060; Thu, 16 Jan 2025 12:46:39 +0000 (UTC) From: Phil Auld To: Alejandro Colomar Cc: linux-man@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v1] sched: Mention autogroup disabled behavior Date: Thu, 16 Jan 2025 12:46:54 +0000 Message-ID: <20250116124654.2365691-1-pauld@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Content-Type: text/plain; charset="utf-8" The autogroup feature can be contolled at runtime when built into the kernel. Disabling it in this case still creates autogroups and still shows the autogroup membership for the task in /proc. The scheduler code will just not use the the autogroup task group. This can be confusing to users. Add a sentence to this effect to sched.7 to point this out. Signed-off-by: Phil Auld To: Alejandro Colomar Cc: Cc: LKML --- man/man7/sched.7 | 2 ++ 1 file changed, 2 insertions(+) diff --git a/man/man7/sched.7 b/man/man7/sched.7 index 71f098e48..f0a708cd7 100644 --- a/man/man7/sched.7 +++ b/man/man7/sched.7 @@ -724,6 +724,8 @@ in the group terminates. .P When autogrouping is enabled, all of the members of an autogroup are placed in the same kernel scheduler "task group". +When disabled the group creation happens as above, and autogroup membership +is still visible in /proc, but the autogroups are not used. The CFS scheduler employs an algorithm that equalizes the distribution of CPU cycles across task groups. The benefits of this for interactive desktop performance --=20 2.47.0