> Why would it not fill the track?

Ken,
at some point it gets down the electro-magneto-mechanical stuff.

Think of a mag tape.   You write a block,  maybe 8K.   Then there's
a mag tape form of inter-record-gap.   If you instead write a 1K block
the inter-record-gap is the same size.   So on tape,  you'd get
less total storage with 1K blocks than with 8K blocks.

Real 3390 DASD are the same in this aspect.   The magnetic markers
between blocks (records) are the same size regardless of the size
of the blocks themselves.   Smaller blocks,  same inter-block gaps.
Dunno why it would be strictly true for contemporary "3390" which are
emulated by 512-byte FBA critters under the covers,
except perhaps to be true to the emulation.

-- R;

Reply via email to