[albatross13]

Now that is cool- I have to ask, is there a moment in your memory where looking back you kind of realized "Wow, I can no longer keep track of everything going on with these computers?" (in regards to it being possible to know how every bit of hardware/software worked).

[segmondy]

It's still possible to do so. Just get an EE degree, you will understand hardware down to the gate level. Take a solid CS course and you will understand software down the basic levels. Understanding hardware to OS is something that a lot of people still know, what is difficult to know these days is the layers of software by 3rd parties running on the OS.

[izzydata]

You can analyze any single part of a modern large piece of software, but I think the point is that you can no longer remember the entirety of the software or hardware. Even a single function is going to get compiled through multiple layers of obfuscation until it hits the hardware and at that point modern CPUs are also extremely convoluted. Nobody is going to know how a function on your OS will compute with absolute certainty.

[kevin_thibedeau]

Not all modern CPUs are high performance devices. In fact the vast majority of microprocessors are no more complicated than an early minicomputer.

[cptnapalm]

From what I've read from others a PDP-8 or maybe a PDP-11 is about the limit. They got a 12-bit computer with 32 KiW to be a time sharing system for 17 users with TSS-8. So they were still quite capable.

[ncmncm]

4k words of RAM, and it ran a Fortran compiler.

[GrumpyYoungMan]

Contrary to some sibling posts, datapath width isn't really the limiting factor for comprehension IMO; everything is "wider" but not more difficult to understand. For example, undergraduate computer engineering students could and did design pipelined in-order 32 bit processors as part of their studies.

At least IMO superscalar + out of order execution was when things really became too complex to hold comprehension of the entire processor in one's head.

[Gordonjcp]

> datapath width isn't really the limiting factor for comprehension IMO

People reckon that changing the head gaskets on an old Rover V8 engine is a complicated and scary job but it's exactly the same as doing it on an old Mini A-series engine, you've just got to do two of them and they're twice as big.