From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lyndon Nerenberg <lyndon@orthanc.ca>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
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Date: Tue,  9 Oct 2018 12:14:03 -0700
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Cc: Lyndon Nerenberg <lyndon@orthanc.ca>
Subject: Re: [9fans] PDP11 (Was: Re: what heavy negativity!)
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hiro writes:

> Huh? What exactly do you mean? Can you describe the scenario and the
> measurements you made?

The big one is USB.  disk/radio->kernel->user-space-usbd->kernel->application.
Four copies.

I would like to start playing with software defined radio on Plan
9, but that amount of data copying is going to put a lot of pressure
on the kernel to keep up.  UNIX/Linux suffers the same copy bloat,
and it's having trouble keeping up, too.

--lyndon