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Date: Sat, 24 Apr 2004 08:18:39 -0700
From: Alfred Perlstein <alfred@freebsd.org>
To: Alexey Dokuchaev <danfe@nsu.ru>
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Subject: Re: bad news for bsdtar..
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* Alexey Dokuchaev <danfe@nsu.ru> [040424 03:14] wrote:
> On Sat, Apr 24, 2004 at 01:59:13AM -0700, Alfred Perlstein wrote:
> > 
> > Have you guys thought of using aio or at least another process
> > to parallelize IO?  (One to read files, and one to write out the
> > archive)
> > 
> > Actually with our kernel threads in 5 you could just use those
> > to speed IO.
> 
> IMHO, still non-blocking/async IO would be faster, and more probably portable,
> unless I'm utterly wrong, of course.  8-)

Threads are pretty portable these days, obviously making it a compile
time option could work, but then again performance would be nice
and it is _our_ tar. ;)

Also, unless you mean 'aio' or 'another process' by "non-blocking/async
IO" then I'm pretty sure you are wrong, as there is no other way
to do this, disk based files do not really support SIGIO (async IO)
or non-blocking IO (NBIO).

-- 
- Alfred Perlstein
- Research Engineering Development Inc.
- email: bright@mu.org cell: 408-480-4684