On Thu, 23 Jun 2005, Joshua Baker-LePain wrote:

Indeed -- the other person referred to the AIT-4 behavior as "DLT
syndrome".  But isn't "variable speed write" different than "writing fill
bytes"?  Does DLT8000 lose capacity when not writing as fast as it can?

Yes.  Same idea.  Tape spins at constant rate, data is written as fast
as possible or else as fast as it comes in.  They probably had some
minimum below which it would stop and restart, but you'd get more on a
tape if you could keep the write buffer from starving.

Actually, with LTO3, I'm a bit worried about keeping the tape streaming
when writing from staged dumps.  Native transfer rate of LTO-3 is stated
as 288 GB/hr, which is about 76 MiB/s.  That's more than most single
spindles can handle, *especially* if you're trying to write to tape while
other dumps are coming in to the holding disk.  Looks like I'll have to do
some work on the server end to really get this thing going.

Wow, that's impressive.  First question is: what does the drive do when
you can't feed it data fast enough?  Depending on the answer you may
or may not actually care enough to worry about it.

-Mitch