[ On Fri, April 3, 1998 at 09:34:08 (+0100), Scott Telford wrote: ]
> Subject: Re: Tape streaming
>
> I tried "buffer", and with a "-u 100" (but not without) that certainly
> made it stream, but when dump writes to stdout it doesn't assume a write
> error implies end-of-tape, which is a bummer.

Yeah, though as I mentioned the NetBSD "dump" doesn't look for EOT
anyway, so there's no loss there.

If double buffering is necessary to copy data between two devices,
esp. when one has removable media, then it does need to be intimately
integrated with the media management.

> However, I tried changing the jumpers on the tape drive to set a 16k
> "disconnect size", rather than 32k as it was before, and this seems to
> do the trick, at least if the disk is otherwise quiescent.

AHHHH!  Sorry!  I forgot all about those silly jumpers.  Yes, using the
largest jumper on the drive (that works), is necessary to achieve good
performance.  Naturally I'd guess my Sun OEM drive is configured thusly,
though I've never opened it up to check.  I've certainly had to do this
on third party drives that I've attached to Suns and other systems
though..

-- 
							Greg A. Woods

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