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 D7379C6FD18 for ; Mon, 6 Mar 2023 03:50:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229662AbjCFDuz (ORCPT ); Sun, 5 Mar 2023 22:50:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229457AbjCFDuy (ORCPT ); Sun, 5 Mar 2023 22:50:54 -0500 Received: from bedivere.hansenpartnership.com (bedivere.hansenpartnership.com [IPv6:2607:fcd0:100:8a00::2]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 246EDC646; Sun, 5 Mar 2023 19:50:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1678074650; bh=uOpjYi/uwBaBMW8bz4zVun2hNpZrW4Dt7bBTAD9vHpA=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=T8lPnbWzdOIza/IhsTAWCawsX4jPwiAZ25CHyR43GLMM+uOn29OwSNeEqsQuwVh0D ETAQy8e7nidLM/i/reZxUWFxis3vec10HQAxcWY28nIvBFIoSLpgklbsFXl0jRK4BR Kt8cjZdreuOEPCRgUZUck9FfeieOYgy7Zit5gke4= Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 9F2E01280671; Sun, 5 Mar 2023 22:50:50 -0500 (EST) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 8kPEqNcgNz3h; Sun, 5 Mar 2023 22:50:50 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1678074650; bh=uOpjYi/uwBaBMW8bz4zVun2hNpZrW4Dt7bBTAD9vHpA=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=T8lPnbWzdOIza/IhsTAWCawsX4jPwiAZ25CHyR43GLMM+uOn29OwSNeEqsQuwVh0D ETAQy8e7nidLM/i/reZxUWFxis3vec10HQAxcWY28nIvBFIoSLpgklbsFXl0jRK4BR Kt8cjZdreuOEPCRgUZUck9FfeieOYgy7Zit5gke4= Received: from lingrow.int.hansenpartnership.com (unknown [IPv6:2601:5c4:4302:c21::a774]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (2048 bits) server-digest SHA256) (Client did not present a certificate) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id 9FCF11280651; Sun, 5 Mar 2023 22:50:49 -0500 (EST) Message-ID: <9bdeda94a7cd2ee9218d992e1da95a322ce0ec68.camel@HansenPartnership.com> Subject: Re: [LSF/MM/BPF TOPIC] Cloud storage optimizations From: James Bottomley To: Matthew Wilcox Cc: Keith Busch , Luis Chamberlain , Theodore Ts'o , lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org Date: Sun, 05 Mar 2023 22:50:48 -0500 In-Reply-To: References: <2600732b9ed0ddabfda5831aff22fd7e4270e3be.camel@HansenPartnership.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.4 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Sat, 2023-03-04 at 16:39 +0000, Matthew Wilcox wrote: > > I fully understand that eventually we'll need to get a single large > > buffer to span discontiguous pages ... I noted that in the bit you > > cut, but I don't see why the prototype shouldn't start with > > contiguous pages. > > I disagree that this is a desirable goal.  To solve the scalability > issues we have in the VFS, we need to manage memory in larger chunks > than PAGE_SIZE.  That makes the concerns expressed in previous years > moot. Well, what is or isn't desirable in this regard can be left to a later exploration. Most of the cloud storage problems seem to be solved with a 16k block size, for which I think we'll find current compaction is good enough. I actually think we might not have a current cloud use case beyond 64k sectors. James