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 0EE4DC7EE24 for ; Mon, 15 May 2023 20:41:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245009AbjEOUk7 (ORCPT ); Mon, 15 May 2023 16:40:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231392AbjEOUk5 (ORCPT ); Mon, 15 May 2023 16:40:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7A57F2D66 for ; Mon, 15 May 2023 13:40:56 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 11DEA61F72 for ; Mon, 15 May 2023 20:40:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D815AC433D2; Mon, 15 May 2023 20:40:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1684183255; bh=Ycz5x4xauJooEI45uTwxsWwrEMcDCoaMGoPeFzflJMw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hBJ5GpTz5XrO2mUy/fQYFQ0hyJ+XYysi2gQscEI7GUVjouJ47/DIBlzXpp1lzgG7V kTfQvrpBvA141MPGgm85yIQC5z+sZTqS1cwPanWA7oqDoiZUTlJRfHy140WZ1m9Bp7 mKTBgYLNqL/DHMbM2714lhYV9RuP6SNC7efBpyAJl2pChTSX30KLHkOr8k7B4XXqQH bnoIE1c9JPp7V+RPG1yHOe94aSbAam3bFAQYq4WpCtiR7NKijOvnBE6WQHVQM9hWjC +VxDlZAQV6H0oGx4BZnfNZmzEcnt2u4CvJkD7JEmIhL7DOpTJSjyZogvhyFFyAn/kZ HBx5z+AllSHkQ== Date: Mon, 15 May 2023 14:40:52 -0600 From: Keith Busch To: jiweisun126@126.com Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, axboe@fb.com, hch@lst.de, sagi@grimberg.me, ahuang12@lenovo.com, sunjw10@lenovo.com Subject: Re: [PATCH] nvme: add cond_resched() to nvme_complete_batch() Message-ID: References: <20230502125412.65633-1-jiweisun126@126.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230502125412.65633-1-jiweisun126@126.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 02, 2023 at 08:54:12PM +0800, jiweisun126@126.com wrote: > From: Jiwei Sun > > A soft lockup issue will be triggered when do fio test on a 448-core > server, such as the following warning: ... > According to the above two logs, we can know the nvme_irq() cost too much > time, in the above case, about 4.8 second. And we can also know that the > main bottlenecks is in the competition for the spin lock pool->lock. The most recent 6.4-rc has included a significant changeset to the pool allocator that may show a considerable difference in pool->lock timing. It would be interesting to hear if it changes your observation with your 448-core setup. Would you be able to re-run your experiements that produced the soft lockup with this kernel on that machine?