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Subject: Re: [Bloat] virtio_net: BQL?
To:     Stephen Hemminger <stephen@networkplumber.org>,
        Dave Taht <dave.taht@gmail.com>
Cc:     Willem de Bruijn <willemdebruijn.kernel@gmail.com>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Xianting Tian <xianting.tian@linux.alibaba.com>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        virtualization <virtualization@lists.linux-foundation.org>,
        bloat <bloat@lists.bufferbloat.net>,
        Jakub Kicinski <kuba@kernel.org>,
        "David S. Miller" <davem@davemloft.net>
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From:   Eric Dumazet <eric.dumazet@gmail.com>
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Date:   Wed, 19 May 2021 16:31:10 +0200
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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.