Magnetic tape filesystem

[Peter Corlett]

On Mon, Feb 09, 2015 at 10:40:06AM -0800, Chuck Guzis wrote:
[...]
> Now, I suspect that the average programmer doesn't worry (or perhaps even
> know about) external sorting what with vast RAM and disk drives,

One still needs to know about external sorts once the data is larger than RAM,
but these days it's often called "Big Data", a term which usually means "I want
to use these sledgehammers on this nut so I can add more buzzwords to my CV".

> but back in the day, it was fascinating.

JOOI, why was there such a need to sort large datasets back in the mainframe
era?