Origin of "partition" in storage devices

[Zane Healy]

On Jan 31, 2022, at 11:28 AM, Paul Koning via cctalk <cctalk at classiccmp.org> wrote:
> 
> Both of these are memory partitions.   The only OS I can think of predating the ones you mentioned is RT-11, the later versions (V2 did not have them).  When did Unix first get partitions?
> 
> 	paul

Partitions are pretty important in RT-11 v5.x, after all, there is the partition size limit, so you have to have multiple partitions for almost any HD, except very small ones.

Let’s not forget hardware enforced partitioning, the WEQSD/04 ESDI controller comes to mind.  It see’s a single large ESDI HD as a single disk, but you can partition it on the controller, and the OS sees each partition as a separate physical disk.  I seem to remember some MFM controllers that made the MFM drive appear to be RL01/RL02 or RK05 packs.

Zane