Message-ID: <1423660672.4847.15.camel@edumazet-glaptop2.roam.corp.google.com> (sfid-20150211_141803_450438_EAAEAD60)
Subject: Re: Throughput regression with `tcp: refine TSO autosizing`
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Michal Kazior <michal.kazior@tieto.com>
Cc: Neal Cardwell <ncardwell@google.com>,
	linux-wireless <linux-wireless@vger.kernel.org>,
	Network Development <netdev@vger.kernel.org>,
	Eyal Perry <eyalpe@dev.mellanox.co.il>
Date: Wed, 11 Feb 2015 05:17:52 -0800
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On Wed, 2015-02-11 at 09:33 +0100, Michal Kazior wrote:

> If I set tcp_limit_output_bytes to 700K+ I can get ath10k w/ cushion
> w/ aggregation to reach 600mbps on a single flow.

You know, there is a reason this sysctl exists in the first place ;)

The first suggestion I made to you was to raise it.

The default setting must stay as is as long default Qdisc is pfifo_fast.

I believe I already mentioned skb->truesize tricks for drivers willing
to adjust the TSQ given their constraints.