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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id EBABBC02188 for ; Mon, 27 Jan 2025 16:24:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7B6C928017F; Mon, 27 Jan 2025 11:24:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 766FD28017A; Mon, 27 Jan 2025 11:24:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6570828017F; Mon, 27 Jan 2025 11:24:10 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 47D8A28017A for ; Mon, 27 Jan 2025 11:24:10 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 023FF1403F9 for ; Mon, 27 Jan 2025 16:24:09 +0000 (UTC) X-FDA: 83053753860.17.DB46DAA Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf10.hostedemail.com (Postfix) with ESMTP id 48A3AC0009 for ; Mon, 27 Jan 2025 16:24:08 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=VzkShxc4; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of kbusch@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kbusch@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1737995048; a=rsa-sha256; cv=none; b=zkHMMY3fWk1r+ulkZaefut4LraQsy62fAaFwZn+ov0b2QGddUZKpD+FzSoYmqa2JyAzKPk i1XlCIjEZdJWwgerdH9kkA0t5ZB7jpYeqUIciFkXbfqr+MERD48whsa//dHhmlieMYyc+y bC3lI0RWQ7kskBdvqZFDorclKrZ22RY= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=VzkShxc4; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of kbusch@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=kbusch@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1737995048; h=from:from:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=S/6tIpWgLUpyghR0G60ouJtT+9Z+qp4+Zo6FGQeYIiA=; b=rso0izCdhSrL3SHfxt+I0flsWlhxkIu9wyttCYkRvJ6ULrDF/VgrwRX4CdoeREDGW9aZmE 7CZe+xQmbx7fPBySAD2mvNfT3Mq7yQAY6ig95L2forL+6dvM8Zw/bdDfuyNnXzAUuXTBC0 Xen/trbxlay3sLQeQp1B4qmgdsupPt4= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 1DB8C5C5880; Mon, 27 Jan 2025 16:23:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6FF58C4CEE0; Mon, 27 Jan 2025 16:24:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737995046; bh=WXa2YJuiY0ajuOmlaEQtEB/6JZudO0/adZLI3G3ihj8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VzkShxc45o6Inpo+sIiqo0h43EnBDypXGHHC/FEVup6W/ufdTLisj0W5T6gIG25hT 18sSWfgzp/I1CVhs9s18clswhZNuwkXVcqzeJoAQPBIDGFpMytdJx/XcrcE2d/zq27 011o9mwkwVpyKxUyTLVYtB4vWbCM2TmW+zaHjW+kQW8mOL//k4owIsyB5K9fOYGvtm m6Aw5s2MNXumD618aVqPvNg9CfInf+uaL4zJLv1oEG4os3wqzcoE4GetoEmiePQDBi EedINY/t5XuZZhkXIpB3l87LD0UDMg+8biV24Q3xKK9M+OZ50ZAyLUuH3xRuqk1syO EBAWWa/HQkXlA== Date: Mon, 27 Jan 2025 09:24:03 -0700 From: Keith Busch To: Matthew Wilcox Cc: David Hildenbrand , linux-mm@kvack.org, linux-block@vger.kernel.org, Muchun Song , Jane Chu , Andres Freund Subject: Re: Direct I/O performance problems with 1GB pages Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 48A3AC0009 X-Stat-Signature: oeh1brbnk1qb6qaewk4bi755eb4hiau1 X-HE-Tag: 1737995048-583126 X-HE-Meta: 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 j1XdOtO6 k0Qg/RtqkgtLZYVyL6Dave6H/ZHGsSvlpXzQxWh0gmdOrs9jm43n1GM8zexAemCzvqlttBKGvy1zic0vzejw1hn34+h+S6jIDzGhq2tPNIY6RY0m0FzTJOpDHUr/Z5kYCrOz3xX261yLBx3pBVWHgjAZGnupkLoR8U5sJH5QsRwnjj4d2CTAb9/VzR8hNJefTQZqtQFw7h1B0H0NGRF5P1AIhxkQh45X0kRQOwKDtFMXpzBi/49kXteJ+49yOqpLnLZeAo+xPWJjMIWR/g/XMHhN7xCPX85siaO0Vx/Masd7uT2wNRztDSWEmsQDzQac8LaxIkYnaX8X6tmldz1MG4acxvg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Jan 27, 2025 at 04:02:41PM +0000, Matthew Wilcox wrote: > Now, since postgres is using io_uring, perhaps there could be a path > which registers the memory with the iouring (doing the refcount/pincount > dance once), and then use that pinned memory for each I/O. Maybe that > already exists; I'm not keeping up with io_uring development and I can't > seem to find any documentation on what things like io_provide_buffers() > actually do. Yes, io_uring does hqve this capability. Here's a doc describing the liburing function that sets it up, and explains how to reference it in subsequent IO: https://unixism.net/loti/ref-liburing/advanced_usage.html#c.io_uring_register_buffers