On 05/10/2018 07:29 AM, Paul Koning via cctalk wrote: > I'm wondering what the reality of fast drum memories looked like, and whether > anyone came even close to these numbers. Also, am I right in thinking they > are at least in principle achievable? I know I could run the stress numbers, > but haven't done so.
All of the STAR-100 stations, including the paging station used drums. Jim Thornton and folks at CDC ADL were working on a 100K RPM drum spinning in vacuo for a paging store, but they couldn't get it to work reliably. At any rate, STAR was the last system I saw fast drums on and you can check the figures in the Bitsavers documentation under cdc/cyber/cyber200. At any rate, a head-per-track drum could be much faster than a disk. There were big slow drums, also. Consider the Univac FASTRAND unit. --Chuck