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 lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (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 8BEA0FB44BB for ; Fri, 24 Apr 2026 06:27:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wGA06-0007AW-IK; Fri, 24 Apr 2026 02:26:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wG9zw-000787-46 for qemu-devel@nongnu.org; Fri, 24 Apr 2026 02:26:45 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wG9zt-0004y0-EA for qemu-devel@nongnu.org; Fri, 24 Apr 2026 02:26:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1777011997; h=from:from:reply-to:subject:subject: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=As3D+yvgCFGoqM3li5vFKulPxLGehH6KxlEEDMA2/M8=; b=JQBCB8SNHNBhI/LMWXlE9xbghPObj/lMC5AXFhV+xLpEFhl0RI/k0azkX922+2kAuwdRij 6p9PXNLJiCzOvVtiUoZH5thzbz/o3G7Ov8gIn3juYv4zMmGeCHLlDjG7RynqAugVWIuVTn xN75ZnojN6wnBTHo1uIiptXGjTKbia8= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-80-L1YkjpH4MR-soD48EwxxwA-1; Fri, 24 Apr 2026 02:26:34 -0400 X-MC-Unique: L1YkjpH4MR-soD48EwxxwA-1 X-Mimecast-MFC-AGG-ID: L1YkjpH4MR-soD48EwxxwA_1777011992 Received: from mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.111]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 160D01956089; Fri, 24 Apr 2026 06:26:32 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.30]) by mx-prod-int-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 1A9F31800446; Fri, 24 Apr 2026 06:26:30 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 7C2D721E6A28; Fri, 24 Apr 2026 08:26:28 +0200 (CEST) From: Markus Armbruster To: Jaehoon Kim Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, pbonzini@redhat.com, stefanha@redhat.com, fam@euphon.net, eblake@redhat.com, berrange@redhat.com, eduardo@habkost.net, dave@treblig.org, sw@weilnetz.de, mjrosato@linux.ibm.com, farman@linux.ibm.com Subject: Re: [PATCH v5 3/3] qapi/iothread: introduce poll-weight parameter for aio-poll In-Reply-To: <20260423195918.661299-4-jhkim@linux.ibm.com> (Jaehoon Kim's message of "Thu, 23 Apr 2026 14:59:18 -0500") References: <20260423195918.661299-1-jhkim@linux.ibm.com> <20260423195918.661299-4-jhkim@linux.ibm.com> Date: Fri, 24 Apr 2026 08:26:28 +0200 Message-ID: <87pl3ox4a3.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.111 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Jaehoon Kim writes: > Introduce a configurable poll-weight parameter for adaptive polling > in IOThread. This parameter replaces the hardcoded POLL_WEIGHT_SHIFT > constant, allowing runtime control over how much the most recent > event interval affects the next polling duration calculation. > > The poll-weight parameter uses a shift value where larger values > decrease the weight of the current interval, enabling more gradual > adjustments. When set to 0, a default value of 3 is used (meaning > the current interval contributes approximately 1/8 to the weighted > average). > > This patch also removes the hardcoded default value checks from > adjust_polling_time(). Instead, poll-grow, poll-shrink, and > poll-weight now use default values initialized in iothread.c > during IOThread creation. > > Signed-off-by: Jaehoon Kim > Reviewed-by: Stefan Hajnoczi QAPI schema Acked-by: Markus Armbruster