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 8E9FAC636CC for ; Sat, 11 Feb 2023 12:06:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229571AbjBKMGn (ORCPT ); Sat, 11 Feb 2023 07:06:43 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229473AbjBKMGn (ORCPT ); Sat, 11 Feb 2023 07:06:43 -0500 Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04E282FCFF; Sat, 11 Feb 2023 04:06:42 -0800 (PST) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id B07645D511; Sat, 11 Feb 2023 12:06:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1676117200; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KP5yy1ZpwWkRzlaqj8fbu7lqqI4sZIjJJyvGJl92ICE=; b=NJPGzvbYh3oTdV5a6oBqeiHxCosJwJPz9/mOLIfh18z09End4DbwW5SJdouu0ILz5CJV12 clfQzgJHB6QG0h+X0c7VwXUqKaT1FeHEcBxJjHK+m42AgkXm110NqKkNzzevLfv3zhrpi7 W4EwKeBQCj9rn2Dn50cTai7hGgAqgVw= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1676117200; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KP5yy1ZpwWkRzlaqj8fbu7lqqI4sZIjJJyvGJl92ICE=; b=U0NL6JPqPuTL8hiRN3SVVvrSEy29wDuJ6zC9OqCxAMM9pZILZX+zx0SGsplJx5RSrfyPU4 SiNrEqQDW86yApBg== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 70E3313A10; Sat, 11 Feb 2023 12:06:40 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id HYO/GtCE52OoXAAAMHmgww (envelope-from ); Sat, 11 Feb 2023 12:06:40 +0000 Message-ID: <87bd6050-d7df-94f6-bfc1-6ddac79d6d65@suse.de> Date: Sat, 11 Feb 2023 13:06:39 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.1 Subject: Re: [LSF/MM/BPF ATTEND][LSF/MM/BPF Topic] Non-block IO Content-Language: en-US To: Kanchan Joshi , lsf-pc@lists.linux-foundation.org Cc: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, io-uring@vger.kernel.org, axboe@kernel.dk, hch@lst.de, kbusch@kernel.org, ming.lei@redhat.com References: <20230210180033.321377-1-joshi.k@samsung.com> From: Hannes Reinecke In-Reply-To: <20230210180033.321377-1-joshi.k@samsung.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 2/10/23 19:00, Kanchan Joshi wrote: > is getting more common than it used to be. > NVMe is no longer tied to block storage. Command sets in NVMe 2.0 spec > opened an excellent way to present non-block interfaces to the Host. ZNS > and KV came along with it, and some new command sets are emerging. > > OTOH, Kernel IO advances historically centered around the block IO path. > Passthrough IO path existed, but it stayed far from all the advances, be > it new features or performance. > > Current state & discussion points: > --------------------------------- > Status-quo changed in the recent past with the new passthrough path (ng > char interface + io_uring command). Feature parity does not exist, but > performance parity does. > Adoption draws asks. I propose a session covering a few voices and > finding a path-forward for some ideas too. > > 1. Command cancellation: while NVMe mandatorily supports the abort > command, we do not have a way to trigger that from user-space. There > are ways to go about it (with or without the uring-cancel interface) but > not without certain tradeoffs. It will be good to discuss the choices in > person. > I would love to have this discussion; that's something which has been on my personal to-do list for a long time, and io_uring might finally be a solution to it. Or, alternatively, looking at CDL for NVMe; that would be an alternative approach. Maybe it's even worthwhile to schedule a separate meeting for it. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew Myers, Andrew McDonald, Martje Boudien Moerman