From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: * X-Spam-Status: No, score=1.9 required=5.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_EF,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.6 Received: from mail-pl1-f182.google.com (mail-pl1-f182.google.com [209.85.214.182]) by gnuweeb.org (Postfix) with ESMTPS id 6568083191 for ; Sun, 26 Feb 2023 17:01:45 +0000 (UTC) Authentication-Results: gnuweeb.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20210112 header.b=IVew+NoK; dkim-atps=neutral Received: by mail-pl1-f182.google.com with SMTP id h8so1105858plf.10 for ; Sun, 26 Feb 2023 09:01:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc:subject:date:message-id :reply-to; bh=0JXRJzGuJZN00HNNHJfRJv3AmmbP6kCQMVWRc0KyX8U=; b=IVew+NoK6l47qKNxcUxWrRlLUX49q+1GN9+96MVBY8nOrJ2SbDHZWLVcf1wYqdb64b MkGa3tmpaY6IELj7MGIc06t4FGMmU1tv+by/+W6G/g49ujYx0QgmwGin1fC3OHqKak8a zQFoyy/ZovVXcUbOHrOyWtDms0dKlBrez+HGvJX5906yrlbogQXEA69hKsxKspOysj4Q MzzhIlZuZrckHi9niouh3+2hYHkCBy1ovVEd6BmFLG8d4vMx3C2NbuT+NkzphH1e2z5r drORQri+P2TV0KN9WpDK97OPTj9WHEjZiDnzLFMJW4C+41isLycNvDfHvBlfyVFFiIAW ql5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0JXRJzGuJZN00HNNHJfRJv3AmmbP6kCQMVWRc0KyX8U=; b=ar9kGqVVR8byd3YVBz5hDP7emp8F37SaEc475QLJMMbeNbqCv3fyISSJkJFteJopYy 5LDGxEbo5tn5zILL6lvFI+DJlAoUFoamcjDxDjmmUfQc0CTBvpDOGkTKycEQo36qDFTQ ouIgFfMov1UG3zqcMToxq/F0YD5BRb6gOte9EDVmLU70vwo0HgPLx+V8sqqdTb0PWr2Z 0KRnj6Dia18TNIY/lEVXt4GDDyQ8+VDyLKDVwuIBkC5j/IbmVqf/SdRrW9ptpwF5tSn/ 4q8RwujQbK5mGB0fwlR6mvNhR77SIx9ZqWOXZH8SIzdBcbmXt1/HtopBvDbg/JrcepvG O51A== X-Gm-Message-State: AO0yUKUgfiMZH0V1ypLYxPbewbM0MysqSL2FRqeOOX+idHEnWhptDYny ypr9nfEN2vrcXjB50JBuOGU= X-Google-Smtp-Source: AK7set+UV26zRGMa1ukPz1jMf2XulekvRMg4op9oeY3PT/q4GbUPnYliVlA3cAiWqq4s8elT6dUYrw== X-Received: by 2002:a17:902:db08:b0:19c:da7f:a237 with SMTP id m8-20020a170902db0800b0019cda7fa237mr9714990plx.5.1677430904423; Sun, 26 Feb 2023 09:01:44 -0800 (PST) Received: from localhost (2603-800c-1a02-1bae-a7fa-157f-969a-4cde.res6.spectrum.com. [2603:800c:1a02:1bae:a7fa:157f:969a:4cde]) by smtp.gmail.com with ESMTPSA id w11-20020a1709029a8b00b0019a7363e752sm2859138plp.276.2023.02.26.09.01.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 26 Feb 2023 09:01:43 -0800 (PST) Sender: Tejun Heo Date: Sun, 26 Feb 2023 07:01:41 -1000 From: Tejun Heo To: Ammar Faizi Cc: Chris Mason , Josef Bacik , David Sterba , Lai Jiangshan , Filipe Manana , Linux Btrfs Mailing List , Linux Kernel Mailing List , Linux Fsdevel Mailing List , GNU/Weeb Mailing List Subject: Re: [RFC PATCH v1 0/6] Introducing `wq_cpu_set` mount option for btrfs Message-ID: References: <20230226160259.18354-1-ammarfaizi2@gnuweeb.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230226160259.18354-1-ammarfaizi2@gnuweeb.org> List-Id: On Sun, Feb 26, 2023 at 11:02:53PM +0700, Ammar Faizi wrote: > Hi, > > This is an RFC patchset that introduces the `wq_cpu_set` mount option. > This option lets the user specify a CPU set that the Btrfs workqueues > will use. > > Btrfs workqueues can slow sensitive user tasks down because they can use > any online CPU to perform heavy workloads on an SMP system. Add a mount > option to isolate the Btrfs workqueues to a set of CPUs. It is helpful > to avoid sensitive user tasks being preempted by Btrfs heavy workqueues. > > This option is similar to the taskset bitmask except that the comma > separator is replaced with a dot. The reason for this is that the mount > option parser uses commas to separate mount options. Hmm... the allowed cpumasks for unbounded workqueues can already be set through /sys/devices/virtual/workqueue/cpumask and also each individual workqueue can be exposed in the matching subdirectory by setting WQ_SYSFS. Wouldn't the proposed btrfs option be a bit reduandant? Thanks. -- tejun