"Bounce buffer" copyright [was Re: flash (or ide) storage for unibus 11?]

Tapley, Mark mtapley at swri.edu
Sun Nov 29 15:03:58 CST 2015


On Nov 29, 2015, at 12:13 PM, Warner Losh <imp at bsdimp.com> wrote:

> A similar thing was implemented on the old DEC Rainbow 100 (though
> I'm sure others). To give the software a chance to do some minor things
> while processing, it physically laid out the 10 sectors as 0 2 3 4 6 8 1 3 5 7 9
> so that when reading sequentially, you had half a disk rotation to get your act
> together to read the next sector. This turned out to be only a small
> performance win, and was a pita for interoperability, 

….but, at least you had a functionally redundant sector 3!

:-)



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