No, the 80s were not 8b. The 68000 was 32b. The 8088 used in the IBM PC was 16b and then quickly changed to 32b with the 80386 in the PC/AT. The Apple II started at 8b but changed to 16b with the IIgs.
I didn't see superscalar mentioned. But I saw some close synonyms; so I'm good.
However, I didn't see μop caches. The x86 tax is pretty small in 2017 and it was pretty expensive in the 80s leaving the door open for RISC. That's definitely missing.
Not all eight bit, but 32 bit was really more of a nineties thing.
The first 386 PC didn't come out until 1987, but hardly anyone had them until about 1990. The 68k was a hybrid 16/32 bit processor, and the IIgs didn't come out until 1987 and hardly anyone bought one.
If you were to go into someone's home or office in 1989 and see how many bits their computer had, it was overwhelmingly likely to have been 8 or 16.
Superscalar is an idealized notion of concurrent instructions per clock, almost MISD. Even the Pentium doesn’t really work like that, where one pipe isn’t fully capable, but it still has OOE, so it’s nothing like the Computer Architecture books with nice two or more concurrent instructions per cycle. In the real-world with OOE, reservation stations, register renaming, retiring and related technologies, it’s hard to say what runs when, but that the scheduler tries to keep execution units as busy as possible given the window of incoming instructions and their branches. There are broadly: 0) single-pipeline, sequential processors and 1) OOE ones with any number of execution units.
Also related: hyperthreading takes idle excution units of a core and makes two virtual processor threads out of them that compete for execution unit scheduling. Slightly faster multiprocessing performance with possibly slightly slower single thread performance.
I think the biggest change is that as long as I follow a set of best practices, I never have to worry about performance. It's always good enough. I can spin up 5 docker containers with a copy of my program running in each, on my 4 year old laptop, and performance is still not an issue.
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[ 4.1 ms ] story [ 29.8 ms ] threadI didn't see superscalar mentioned. But I saw some close synonyms; so I'm good.
However, I didn't see μop caches. The x86 tax is pretty small in 2017 and it was pretty expensive in the 80s leaving the door open for RISC. That's definitely missing.
The first 386 PC didn't come out until 1987, but hardly anyone had them until about 1990. The 68k was a hybrid 16/32 bit processor, and the IIgs didn't come out until 1987 and hardly anyone bought one.
If you were to go into someone's home or office in 1989 and see how many bits their computer had, it was overwhelmingly likely to have been 8 or 16.
Also related: hyperthreading takes idle excution units of a core and makes two virtual processor threads out of them that compete for execution unit scheduling. Slightly faster multiprocessing performance with possibly slightly slower single thread performance.