It isn’t a disk driver since the OS is not loaded yet. It is the hardware identifying each disk in the SCSI chain. Not sure what else it was doing walking the bus much I know finding all the disk was the longest part.
Shoot, it did occur to me that might not technically be the right word.
Still, even if you’re an engineer in the late 80’s, it seems like it would be obvious you need a way for disks to announce themselves in O(1) time. Was it just a limitation of interoperability between vendors or something?
I think it was just a limit of how quick everything ran back then. Also, this was an IBM system that was checked, double-checked, and triple-checked because it was a mission-critical system. IBM used to be known for quality hardware. Hard to imagine because they are such a crap company now but that was the equivalent of a google back then.
