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Date: Mon, 23 Jul 2012 09:41:18 +0200 (CEST)
From: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>
To: Jakub Lach <jakub_lach@mailplus.pl>
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Cc: freebsd-questions@freebsd.org
Subject: Re: "da0: 40.000MB/s transfers" What was rationale behind pegging
 USB 2.0 at 40MB/s?
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> And USB 2.0 hard limit is 60MB/s.
i have never seen USB 2.0 exceeding 35MB/s write and 40MB/s read.

even when connecting SATA disk over USB-SATA bridge.

60MB/s is wire speed. USB have enormous protocol overhead.