3 ms·
> no-one wanted to run anything other than rather specialised programs on a Cray 1 or any of its descendants because it was just not very fast for that That’s
by pinewurst 5y ago
> no-one wanted to run anything other than rather specialised programs on a Cray 1 or any of its descendants because it was just not very fast for that
That’s not at all true. Cray-1 and immediate descendants were just as good at scalar workloads as vector (their killer advantage over the likes of STAR-100 etc). Their major issues came from having crummy early 1960s-style memory management - never really fixed - making them pretty awful Unix (or even just shared) machines. As effectively single threaded workload batch targets under COS (regurgitated CDC yuck) they were the awesome Fortran machines they were designed to be.
- wumpus 5y agoI used Crays under Unicos for quite a while and they weren't crummy at all... given a batch-oriented scientific workload. Even though the memory management was antiquated, there was an enormous, fast swap device available on every vector Cray.
- pinewurst 5y agoBut users were always hitting that device making it a bottleneck as job sizes grew, at least in my experience. Swap isn’t partial either, just roll out, roll it. Lustre btw was originally designed as a networked substitute HPC swap - the source of many original issues. I didn’t say Unicos was crummy - it was the feel of the system with more than a small few on it.
- wumpus 5y agoIt had amazing bandwidth to the swap device, so no, I've never seen interactive use be slow. Of course that's just my actual usage (NCSA, SDSC, Stennis, etc) and not the only possible experience.