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Date:   Mon, 29 Nov 2021 07:57:07 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     menglong8.dong@gmail.com
Cc:     davem@davemloft.net, yoshfuji@linux-ipv6.org, dsahern@kernel.org,
        edumazet@google.com, imagedong@tencent.com, ycheng@google.com,
        kuniyu@amazon.co.jp, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org
Subject: Re: [PATCH v2 net-next] net: snmp: add statistics for tcp small
 queue check
Message-ID: <20211129075707.47ab0ffe@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
In-Reply-To: <20211128060102.6504-1-imagedong@tencent.com>
References: <20211128060102.6504-1-imagedong@tencent.com>
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On Sun, 28 Nov 2021 14:01:02 +0800 menglong8.dong@gmail.com wrote:
> Once tcp small queue check failed in tcp_small_queue_check(), the
> throughput of tcp will be limited, and it's hard to distinguish
> whether it is out of tcp congestion control.
> 
> Add statistics of LINUX_MIB_TCPSMALLQUEUEFAILURE for this scene.

Isn't this going to trigger all the time and alarm users because of the
"Failure" in the TCPSmallQueueFailure name?  Isn't it perfectly fine
for TCP to bake full TSQ amount of data and have it paced out onto the
wire? What's your link speed?