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 X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D090CC432BE for ; Tue, 31 Aug 2021 09:59:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFD1060F6C for ; Tue, 31 Aug 2021 09:59:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240787AbhHaKA0 (ORCPT ); Tue, 31 Aug 2021 06:00:26 -0400 Received: from smtp-out2.suse.de ([195.135.220.29]:59436 "EHLO smtp-out2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240774AbhHaKAZ (ORCPT ); Tue, 31 Aug 2021 06:00:25 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (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 EFCF41FE68; Tue, 31 Aug 2021 09:59:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1630403969; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=lx70k8u2MAA5RCAXK67RBAT4TDGyen08WXhc6Uhjfoc=; b=Kz3ZAFEhjEAqzoVpfddcZcOe8ZOpkR70+40CSI+n7SgGS4DFGJaRusuqHiGN6vcz8twCKK cM12pL72UUT4XqSHs78qHPHjI/qrqCKfaFHAZhqaO2JdyACfNaeBrVZPG7pZoOBWqih6tq zlTmqD4lp5WVRZaNqeg8osbWye9wl64= Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (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 imap1.suse-dmz.suse.de (Postfix) with ESMTPS id D444913A64; Tue, 31 Aug 2021 09:59:29 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id phzfMoH9LWEedQAAGKfGzw (envelope-from ); Tue, 31 Aug 2021 09:59:29 +0000 Date: Tue, 31 Aug 2021 11:59:30 +0200 From: Michal =?iso-8859-1?Q?Koutn=FD?= To: Paolo Valente Cc: Jan Kara , Jens Axboe , linux-block@vger.kernel.org Subject: Re: [PATCH 0/3 v2] bfq: Limit number of allocated scheduler tags per cgroup Message-ID: <20210831095930.GB17119@blackbody.suse.cz> References: <20210715132047.20874-1-jack@suse.cz> <751F4AB5-1FDF-45B0-88E1-0C76ED1AAAD6@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <751F4AB5-1FDF-45B0-88E1-0C76ED1AAAD6@linaro.org> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hello Paolo. On Fri, Aug 27, 2021 at 12:07:20PM +0200, Paolo Valente wrote: > Before discussing your patches in detail, I need a little help on this > point. You state that the number of scheduler tags must be larger > than the number of device tags. So, I expected some of your patches > to address somehow this issue, e.g., by increasing the number of > scheduler tags. Yet I have not found such a change. Did I miss > something? I believe Jan's conclusions so far are based on "manual" modifications of available scheduler tags by /sys/block/$dev/queue/nr_requests. Finding a good default value may be an additional change. (Hopefully this clarifies a bit before Jan can reply.) Michal