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=-1.0 required=3.0 tests=MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 9E032C33CB6 for ; Wed, 22 Jan 2020 11:59:30 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6D14F24685 for ; Wed, 22 Jan 2020 11:59:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6D14F24685 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 109516B0005; Wed, 22 Jan 2020 06:59:30 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0B9FC6B0008; Wed, 22 Jan 2020 06:59:30 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F12536B0005; Wed, 22 Jan 2020 06:59:29 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0040.hostedemail.com [216.40.44.40]) by kanga.kvack.org (Postfix) with ESMTP id D834F6B0007 for ; Wed, 22 Jan 2020 06:59:29 -0500 (EST) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id 8AE3E181AEF10 for ; Wed, 22 Jan 2020 11:59:29 +0000 (UTC) X-FDA: 76405125258.25.CB2F6FB Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id 68F411804E3A1; Wed, 22 Jan 2020 11:59:29 +0000 (UTC) X-HE-Tag: stone21_35ac7dd25f45d X-Filterd-Recvd-Size: 2891 Received: from mail-wm1-f65.google.com (mail-wm1-f65.google.com [209.85.128.65]) by imf29.hostedemail.com (Postfix) with ESMTP; Wed, 22 Jan 2020 11:59:28 +0000 (UTC) Received: by mail-wm1-f65.google.com with SMTP id q9so6516325wmj.5; Wed, 22 Jan 2020 03:59:28 -0800 (PST) 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; bh=BhxPVdDn3Z4CWsuQOzp+pXDi/cOhHkkVUOHbOPLR28k=; b=mqxWya7ljt547wur8lCMmgwDAVFmFxY0HFdOWcXHBB1dDkkqnPM1qsWNUm4KMhMzjM PedusyNePN4KKMK+0SQ8XIgcJsmUlzkR9UkxB5YuyaiRWriiXHLLzxLNJsSQD08xaBD+ fxBJ91Uuahs+KT2JhwjVPyetUWce6xSAoiDoYQYAQwxbdGEmnfkD/yMJ6j11XGSpBm+m LfLKeM4rM/K2ueZQXAJBubd+yqQ4Pf/Td56Nr3Y77GIiBC52kt+vgeWfusj5VYG2Pb7l +/ErxFB/Wz2qxd86law59en/P307Bj6EPZNtckEUsZ+B64nNuq7Bnf6WdF3xCmHyfjCo 4dDA== X-Gm-Message-State: APjAAAXw4/QJUAXMsAq77HWTssemiaiUVVu/qlXn+FG86wS3I0YaT6dL tOqfu7yHroqypTdsL9bkO/I= X-Google-Smtp-Source: APXvYqy5pWrmdMYHeRQcPqrPAInWTrBV+N316JaWfM3TKaooeOlM7u5oTbqt/HE5mt0+7pDPdJrEpg== X-Received: by 2002:a7b:c851:: with SMTP id c17mr2581017wml.71.1579694367672; Wed, 22 Jan 2020 03:59:27 -0800 (PST) Received: from localhost (prg-ext-pat.suse.com. [213.151.95.130]) by smtp.gmail.com with ESMTPSA id p17sm3638585wmk.30.2020.01.22.03.59.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Jan 2020 03:59:27 -0800 (PST) Date: Wed, 22 Jan 2020 12:59:26 +0100 From: Michal Hocko To: Jerome Glisse Cc: Jens Axboe , lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Benjamin LaHaise Subject: Re: [LSF/MM/BPF TOPIC] Do not pin pages for various direct-io scheme Message-ID: <20200122115926.GW29276@dhcp22.suse.cz> References: <20200122023100.75226-1-jglisse@redhat.com> <20200122045723.GC76712@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200122045723.GC76712@redhat.com> X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue 21-01-20 20:57:23, Jerome Glisse wrote: > We can also discuss what kind of knobs we want to expose so that > people can decide to choose the tradeof themself (ie from i want low > latency io-uring and i don't care wether mm can not do its business; to > i want mm to never be impeded in its business and i accept the extra > latency burst i might face in io operations). I do not think it is a good idea to make this configurable. How can people sensibly choose between the two without deep understanding of internals? -- Michal Hocko SUSE Labs