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Date: Fri, 12 Dec 2008 19:47:38 +0200
From: Danny Braniss <danny@cs.huji.ac.il>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: preventing FIFO from EOF 
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> > BTW, buffer was written way back when memory was measured
> > in kilobytes and the ethernet was 10 mgb, so things have changed a bit, and
> > its effectivness is questionable :-)
> > 
> My scenario:
> 
> prog1 | prog2
> 
> where both are daemons. prog1 does all the work, and sends commands for 
> prog2 to do when needed. I don't want prog1 to block while prog2 is busy 
> executing the command. So a buffer is inserted between the two:
> 
> prog1 | buffer | prog2
> 
> Asynchronous execution of commands. It's as simple as that.

ahh, but you see, you have now 4 processes, which the scheduler has no
real reason to treat specialy, each can block. Then again, I have
no idea how much data you are moving around, and how fast you need
to process it. buffer was designed to keep a magnetic tape writing
at full speed - streaming, or at least for some longer time.
then again, there is nothing better than trying it out, instead
of out guessing the os :-)

cheers,
	danny