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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1DED7CA5FED for ; Tue, 6 Oct 2026 11:03:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=+kjweTI65fcbDGIFtPcxvD1ult6uA10dTL5DcUau8hA=; b=KcYyADcjZ8y1OoXr4JPQZkzIsw QtcRdhpEt6ykcua9LnAP3VCx/0nRfmADA0faxTu9LUD5lVJk6VyQ/7YHokcScUV5PB8zEpduDvkLT VA6b1iXB1zaeCa7/+z43EGQGAPneahyJtfFy8PmyWTv26VadskCR3ChzYQuwqqBw2KF+TvBOOuJdM 08axh4O3LgEXMv/PqHuRq2HcsKhtunxuCJVdQ+g1Cw0EUr2FqfpxdVPmSmysaa5/xS4ixIu1yqMoY cMAYS2EDwi7m3l6LKWfvD4WTSxAONZImrpy6rSu6V0fyoAAd+31J9hJGFX7d1un5d0qoQHXjPFcQ0 xeoUvlJg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xE2x1-00000000aQc-2xPT; Tue, 06 Oct 2026 11:03:15 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xE2ww-00000000aQK-2XvV for linux-nvme@lists.infradead.org; Tue, 06 Oct 2026 11:03:10 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id A716B6022C; Tue, 6 Oct 2026 11:03:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 09BD81F000FF; Tue, 6 Oct 2026 11:03:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791284589; bh=+kjweTI65fcbDGIFtPcxvD1ult6uA10dTL5DcUau8hA=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=L4JO7IKLvVg0/a/cdjG1WSVN16TXYE1A17K33VozE4sp1w4Vsj3CtYl7P32phXSVj DraZZcflmOIbvxfyEc+RUjxeRC7CpmOd0mo/+MrePIDydNfON0sqzNaePHSGI9QzeE Z5FJ0x5ka8DhYrFKMGXS1UYOqmjRUrsnOxqpJbQV79g7UAzLgQAcadafPOc25QZxwR RRh3Z9t/AMC8emXwj6ljc1HZCruRCVSFqnMbAATxBJECQMD4NKrNIeea0UATkZl15S hFV5YFtReHmUy6LlgWmcLgoBrf4evT6qTG+XlhRPelj+4FpQszVDQKBq8S6zyEoHe0 6xfH+60lie4sg== Date: Tue, 6 Oct 2026 13:03:04 +0200 From: Keith Busch To: Hannes Reinecke Cc: Keith Busch , linux-nvme@lists.infradead.org, sagi@grimberg.me, hch@lst.de, axboe@kernel.dk Subject: Re: [PATCH RFC] nvme-tcp: allow multiple queues per hctx Message-ID: References: <20260903152623.614951-1-kbusch@meta.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Mon, Sep 21, 2026 at 11:29:40AM -0600, Keith Busch wrote: > I'm still trying to see if we can achieve a similar result just by > making duplicate connections and letting the multipath policy handle the > spread. That does improve things significantly, but I'm getting worse > performance than this RFC, and I still don't know why yet. Best I can tell, the duplicate multipath connections does what's desired on the host side, but the target side (standard Linux in-kernel target) ends up queueing all its work on the same CPU, so that appears to be why my RFC is showing better performance.