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The Legacy of CPU Features Since 1980s
jones_supa writes: David Albert asked the following question:
"My mental model of CPUs is stuck in the 1980s: basically boxes that do arithmetic, logic, bit twiddling and shifting, and loading and storing things in memory. I'm vaguely aware of various newer developments like vector instructions (SIMD) and the idea that newer CPUs have support for virtualization (though I have no idea what that means in practice). What cool developments have I been missing? "
An article by Dan Luu answers this question and provides a good overview of various cool tricks modern CPUs can perform. The slightly older presentation Compiler++ by Jim Radigan also gives some insight on how C++ translates to modern instruction sets.
"My mental model of CPUs is stuck in the 1980s: basically boxes that do arithmetic, logic, bit twiddling and shifting, and loading and storing things in memory. I'm vaguely aware of various newer developments like vector instructions (SIMD) and the idea that newer CPUs have support for virtualization (though I have no idea what that means in practice). What cool developments have I been missing? "
An article by Dan Luu answers this question and provides a good overview of various cool tricks modern CPUs can perform. The slightly older presentation Compiler++ by Jim Radigan also gives some insight on how C++ translates to modern instruction sets.
The first large scale availability of virtualisation was with the IBM 370 series, dating from June 30, 1970, but it had been available on some other machines in the 1960's.
So the idea that "newer machines have support for virtualisation" is a bit old.
Watch this Heartland Institute video
I remember when VMWare first came out, and there was all this amazement about all the cool things you could do with Virtual Machines. Very little mention anywhere that these were things you could do for decades already on mainframes.
Same thing with I/O offloading (compared to mainframes, x86 and UNIX I/O offload is still quite primitive and rudimentary), DB-based filesystems (MS has been trying to ship one of those for over 20 years now; IBM has been successfully selling one (the AS/400 / iSeries) for 25, built-in encryption features, and a host of other features.