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 ws5-mx01.kavi.com (ws5-mx01.kavi.com [34.193.7.191]) (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 560E9C41535 for ; Fri, 22 Dec 2023 08:26:28 +0000 (UTC) Received: from lists.oasis-open.org (oasis.ws5.connectedcommunity.org [10.110.1.242]) by ws5-mx01.kavi.com (Postfix) with ESMTP id 844C526A45 for ; Fri, 22 Dec 2023 08:26:27 +0000 (UTC) Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 677B0986603 for ; Fri, 22 Dec 2023 08:26:27 +0000 (UTC) Received: from host09.ws5.connectedcommunity.org (host09.ws5.connectedcommunity.org [10.110.1.97]) by lists.oasis-open.org (Postfix) with QMQP id 5660C98427C; Fri, 22 Dec 2023 08:26:27 +0000 (UTC) Mailing-List: contact virtio-comment-help@lists.oasis-open.org; run by ezmlm List-ID: Sender: Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id 476909865C1 for ; Fri, 22 Dec 2023 08:26:27 +0000 (UTC) X-Virus-Scanned: amavisd-new at kavi.com X-MC-Unique: lHlUdSdfMVW2YpcXYAnW-Q-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703233584; x=1703838384; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=EHjBNu7CW/gq0Xsdm6UIvrplnHeHn5GZ7bM9BIWgjlA=; b=sy8bSsNfMHDuO73xyjpfI86CgDWpLqCHBJk4vhSBhz2K+AhgYt/hdcLE0MIXnmsKTe ZV+hrZPDxFTxc5Cc/RodXRU85GQ8pzHEBqj6uN0IVbMGeXLyMSGKGGo9JneejWgDRiDk okZ9MPwdK/tqKSf46y4gQQgU/iees2gAxtOnpuO1tnkqv7XwnKCkMNKi9TAOcyG4ZiX3 gyzst7qjbW3mL7DZ4J0PPdbGg3Yk6ZvTE2tlihrgZnuRqO4e7ZRTdrSgzsfPJ2vSVMoC S1/bLEUGI6cUi0FE0K6dxDlfqhSZiM89f5gh/b3y3C/T5n7h8fO+mv+eIwh8sFTDwY2g Zu3Q== X-Gm-Message-State: AOJu0YxhlBAYDJPYsIXPWzUXhY1AEgv2R1bOppcD1B3c77ysCW0NPkEj FiaLMWWtS1Spalo+FqS6+UoSYu13SQFP+V4AuuufBfWU1K9Hxt3GGr8RziObd1xQYM5nQmff3ZR OMG4hsQOY1oeDGCNyT0XDmjSJneJ8MY9hlx8vmF/loA== X-Received: by 2002:a05:600c:1d14:b0:40b:32e7:2ffa with SMTP id l20-20020a05600c1d1400b0040b32e72ffamr590534wms.20.1703233583835; Fri, 22 Dec 2023 00:26:23 -0800 (PST) X-Google-Smtp-Source: AGHT+IEu2gE33La5WnHuWag0w1yHceOf9p3a+xVgaDVVZASn7pCD5Q7UfN0SZVwEWAT5AeLlt+0ltA== X-Received: by 2002:a05:600c:1d14:b0:40b:32e7:2ffa with SMTP id l20-20020a05600c1d1400b0040b32e72ffamr590525wms.20.1703233583508; Fri, 22 Dec 2023 00:26:23 -0800 (PST) Date: Fri, 22 Dec 2023 03:26:20 -0500 From: "Michael S. Tsirkin" To: Jason Wang Cc: Heng Qi , virtio-comment@lists.oasis-open.org, Yuri Benditovich , Xuan Zhuo Message-ID: <20231222032455-mutt-send-email-mst@kernel.org> References: MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Subject: [virtio-comment] Re: [PATCH RESEND] virtio-net: support setting coalescing params for multiple vqs On Thu, Dec 21, 2023 at 11:37:17AM +0800, Jason Wang wrote: > On Wed, Dec 20, 2023 at 10:40 PM Heng Qi wrote: > > > > Currently, when each time the driver attempts to update the coalescing parameters > > for a vq, it needs to kick the device and wait for the ctrlq response to return. > > > > If a command can only update one vq parameters, when the parameters are updated > > frequently (such as netdim), ctrlq on the device is kicked frequently, which will > > increase the device CPU scheduling overhead, and the number and overhead of device > > DMA will also increase. > > > > Merging multiple vq updated parameters into one command can effectively reduce > > the number of kick devices and device DMA times. > > > > Test results show that this greatly improves the efficiency of the ctrlq in > > responding to multiple vq coalescing parameter updates issued by the driver. > > So netdim is per virtqueue, to make use of this, you need to batch the > netdim requests first. And if you do that, you can batch the commands > as well. Then you get one kick for sevreal coal requests? > > Or are you saying you run out of ctrl vq? > > Thanks I think Heng is saying ctrl vq implementation on this DPU is so bad, you need to avoid that as much as possible. -- MST This publicly archived list offers a means to provide input to the OASIS Virtual I/O Device (VIRTIO) TC. In order to verify user consent to the Feedback License terms and to minimize spam in the list archive, subscription is required before posting. Subscribe: virtio-comment-subscribe@lists.oasis-open.org Unsubscribe: virtio-comment-unsubscribe@lists.oasis-open.org List help: virtio-comment-help@lists.oasis-open.org List archive: https://lists.oasis-open.org/archives/virtio-comment/ Feedback License: https://www.oasis-open.org/who/ipr/feedback_license.pdf List Guidelines: https://www.oasis-open.org/policies-guidelines/mailing-lists Committee: https://www.oasis-open.org/committees/virtio/ Join OASIS: https://www.oasis-open.org/join/