From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x435.google.com (mail-wr1-x435.google.com [IPv6:2a00:1450:4864:20::435]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id E22C13B29D for ; Wed, 19 May 2021 10:31:14 -0400 (EDT) Received: by mail-wr1-x435.google.com with SMTP id i17so14237045wrq.11 for ; Wed, 19 May 2021 07:31:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=/uIuAty7PjxXFt4IM0i+V1A/dMXLvYisaqsv/qbrezE=; b=W+/COpqc5fQ8jmoquxbMKC6Ehnr83ZF2XRb52KqwZYN7L9L0nJoj8xNIabgDHYxZU0 F6iZlhockfTfVVlBkn4ud9d63iT87RLJhl0WQV+OQVc0Z9lsHJAAuhWChvkIKFxDEhLd Xoa9cvo6JnHyS6iHtnXsHKHp+ZdMGxHsp/sajjaTvDNFprJ9bSOJGFyOiuU3cfWjhy2C YskgE3TmZMU/r5Xd90LTUeyiE4CVC0A4tBp0aekOUo+UNVY56u8W9gQ6fkhcO9VfRGSx GzoIvK4VI42X9hGqwFgF2D24x6CNomcKUJUvFaU7WURaHypRYJQvhdgxRr44O6trhOlA fB2w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=/uIuAty7PjxXFt4IM0i+V1A/dMXLvYisaqsv/qbrezE=; b=OfZQUYEgXEHmLbcma7kjZqDX0TxDywJDKpd8HnwCVguCSmRR1Fnf150HEXmi+Hy91B zWuueY8VQnZDoPu1kB3zPu6gn3s/Ni5knG8OjO3pgH9+G+uW4NA1rWZtOWxerrzyzzFW rw5DZapmexsDtcJN+lXnpxTAyu4KVFrESbnksFw8pCIVT71WAghvbqo3i1WnoamBb1JG OqVnRbUaPArFlqA2ukaJrFR+02U+pSD/qoYdctv3qQALv3I3ZKmhPPppeI0jjDdC1vvH hxs7Sbj4nZlryUtQ6enfruAKKWIXt/2BMJgLCkYnq913GfmZf6hyG036klsgroLJEGMq 4lbQ== X-Gm-Message-State: AOAM531mHjTMEXJ9HO+P0pxCv/FeqTRpVEzqE+oTA2bqeo91QRLJdVyI z283oc39FlBTqGPYROsuQag= X-Google-Smtp-Source: ABdhPJyXuJnhzN0eu3ei8cGd0y+n4IYYl4B39s4zlfx5aYYQ7hSLjMfpxGTJMNX9DJK1bCo8vkyTLw== X-Received: by 2002:a5d:508e:: with SMTP id a14mr14900327wrt.88.1621434674015; Wed, 19 May 2021 07:31:14 -0700 (PDT) Received: from [10.0.0.2] ([37.172.163.196]) by smtp.gmail.com with ESMTPSA id c6sm7693369wru.50.2021.05.19.07.31.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 19 May 2021 07:31:12 -0700 (PDT) To: Stephen Hemminger , Dave Taht Cc: Willem de Bruijn , "Michael S. Tsirkin" , Xianting Tian , Linux Kernel Network Developers , LKML , virtualization , bloat , Jakub Kicinski , "David S. Miller" References: <56270996-33a6-d71b-d935-452dad121df7@linux.alibaba.com> <20210517160036.4093d3f2@hermes.local> From: Eric Dumazet Message-ID: Date: Wed, 19 May 2021 16:31:10 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.0 MIME-Version: 1.0 In-Reply-To: <20210517160036.4093d3f2@hermes.local> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Bloat] virtio_net: BQL? X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 May 2021 14:31:15 -0000 On 5/18/21 1:00 AM, Stephen Hemminger wrote: > > The Azure network driver (netvsc) also does not have BQL. Several years ago > I tried adding it but it benchmarked worse and there is the added complexity > of handling the accelerated networking VF path. > Note that NIC with many TX queues make BQL almost useless, only adding extra overhead. We should probably make BQL something that can be manually turned on/off.