4 ms·
You bring up a fair point but tapes not really infinitely rewritable. You can take something like a 60's PDP-8 and write a byte of data to the same core addres
by VLM 9y ago
You bring up a fair point but tapes not really infinitely rewritable. You can take something like a 60's PDP-8 and write a byte of data to the same core address 333 thousand times per second for at least half a century and it'll be fine. In my head that's a 14 or 15 digit number of writes which no tape or even flash memory can withstand.
In theory much like a hard drive head floats on an air bearing over the platter it should be possible given enough development time and money to make a tape head that floats and never quite touches tape. I worked at a place in the 90s that had IBM floating tape transport where compressed air maintained some loops bouncing in channels to make sure the tape was never snapped taut and therefore stretched but I'm taking about actually floating a non-contract head which AFAIK has never commercially shipped for tape (although it would be cool to be proven wrong).
I was going to bring up how tape can throw oxide after a couple decades in storage but I suppose core could have dissimilar metal corrosion over the course of a century or maybe temperature cycles would stress and crack individual cores after a couple centuries unless kept at a constant temp. Also in theory non-archival core could exist just like non-archival tape definitely exists. So fair enough on that account.