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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0398CC77B75 for ; Tue, 18 Apr 2023 04:31:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230000AbjDREbe (ORCPT ); Tue, 18 Apr 2023 00:31:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229518AbjDREbc (ORCPT ); Tue, 18 Apr 2023 00:31:32 -0400 Received: from mail-yb1-xb33.google.com (mail-yb1-xb33.google.com [IPv6:2607:f8b0:4864:20::b33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2C05E42 for ; Mon, 17 Apr 2023 21:31:31 -0700 (PDT) Received: by mail-yb1-xb33.google.com with SMTP id b10so233144ybk.9 for ; Mon, 17 Apr 2023 21:31:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1681792291; x=1684384291; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=8t7utIVn1NZcTfXhQfNQOixZnM/sHw7ItMZQq+M8aPc=; b=Cz9/Rr66vJy1JpuaPb/lZt+BqnIAULlsh/bMEJz7lecp7j2/VqIYFP9lYDAXo/GSOe jXegQSsMedSgQT77EeJ2KmfvMzZN6Ljv1+TN3WRsPIfy+i2b79tjjoDydxB2muV0m95F TkPvSFKMkzafvTvvY78d+3eTyLdggNl0pJ/8IVftS/PK5rnOzysZHuDvNz2HHgSEmlTM IFQJtX1mLDjgI+uRRoYmhs70M5a/m3OoBKLn7JyDtPchNoL/b66Hu6xw8kf3RtaIiqXk vwbDlDQqWGfOs1MddFqSn7e1o1bZyRAEkBxq9S98SAthePpj17XI8RVCikHwVaPs+HYc nxOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681792291; x=1684384291; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=8t7utIVn1NZcTfXhQfNQOixZnM/sHw7ItMZQq+M8aPc=; b=MbB1I3WJ3TiUvOwNdIl8xTR56aGiGpxJNlKcq0VnHXcCBMRIAlw2GFfZPuzpAoPOTM jnOrp7qRS5GgsKnCBqtwz0XMNV0aIbkkkdhA+crb67gH4fYoPq7UVo4K13CwgZgMJVUs QVrI61PiU3KtUpLIWHj65rK9rs4835nQTAY2uBaHjdrGqXSeVsUVQgXGgkQ2iy/rf6t0 oZM2tkVdrUxaR/CCXfFVkeg/Yh7tai+jUIy6AH9CE59lSqBTF6NsqlaMViFIWRMS6u1g DvKoAnMhCSmi4rfqtve8XnfhRlOj/nHotPM5rPoOkVTyUGM0nNWvNzbjskVXkl4aZQWR C0jw== X-Gm-Message-State: AAQBX9fwjzjC5gwQK2FOAFuEc9lHTRIc3cRA39XdX0lu0Zwa2wIbN5Xm ONRC2RsIWXWSlwAHLrZsG6xXbQ== X-Google-Smtp-Source: AKy350bkagPcqZa3+5HDiDrj30dc80d8tI3FGCtUz+bHwJx733EmHG6BEvt4HtTfYB6l5+wXa/Zlqg== X-Received: by 2002:a25:e706:0:b0:b8f:44bc:c4f9 with SMTP id e6-20020a25e706000000b00b8f44bcc4f9mr15495368ybh.32.1681792290910; Mon, 17 Apr 2023 21:31:30 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id 185-20020a2506c2000000b00b8f2d726471sm3464611ybg.3.2023.04.17.21.31.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Apr 2023 21:31:30 -0700 (PDT) Date: Mon, 17 Apr 2023 21:31:20 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Luis Chamberlain cc: hughd@google.com, akpm@linux-foundation.org, willy@infradead.org, brauner@kernel.org, linux-mm@kvack.org, p.raghav@samsung.com, da.gomez@samsung.com, a.manzanares@samsung.com, dave@stgolabs.net, yosryahmed@google.com, keescook@chromium.org, patches@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/6] tmpfs: add the option to disable swap In-Reply-To: <20230309230545.2930737-1-mcgrof@kernel.org> Message-ID: <3382819f-4a4-8622-5642-78c03ecfb878@google.com> References: <20230309230545.2930737-1-mcgrof@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 9 Mar 2023, Luis Chamberlain wrote: > I'm doing this work as part of future experimentation with tmpfs and the > page cache, but given a common complaint found about tmpfs is the > innability to work without the page cache I figured this might be useful > to others. It turns out it is -- at least Christian Brauner indicates > systemd uses ramfs for a few use-cases because they don't want to use > swap and so having this option would let them move over to using tmpfs > for those small use cases, see systemd-creds(1). Thanks for your thorough work on tmpfs "noswap": seems well-received by quite a few others, that's good. I've just a few comments on later patches (I don't understand why you went into those little rearrangements at the start of shmem_writepage(), but they seem harmless so I don't object), but wanted to ask here: You say "a common complaint about tmpfs is the inability to work without the page cache". Ehh? I don't understand that at all, and have never heard such a complaint. It doesn't affect the series itself (oh, Andrew has copied that text into the first patch), but please illuminate! Thanks, Hugh