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To: julian@elischer.org
From: "M. Warner Losh" <imp@bsdimp.com>
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Subject: Re: speeding up ugen by an order of magnitude.
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In message: <Pine.BSF.4.21.0407071137440.80217-100000@InterJet.elischer.org>
            Julian Elischer <julian@elischer.org> writes:
: > Nevertheless I see ugen more as a quick and dirty way to test drive a
: > device from userland with all it's great debugging capabilities before
: > writing a specific kernel driver.
: > The requirement that ugen has to be generic is often bad for
: > performance sensitive applications.
: 
: Ugen is used in production all over the place where people have to used
: devices there is no specific support for, and where there is no
: kernel expertise.

usb drivers are very easy to write.  I think that making it easier to
write those drivers is going to be better for the project in the long
run.

ugen is supposed to be general.  If we can make it faster w/o
sacrificying this generalness, that's OK.  But if we can't, then you
gotta do stuff in the kernel.  That's always been the case (and why we
don't have userland tcp, for example).  Some things have to be in the
kernel to be fast.

Warner