That does not seem like particularly notable example of foresight & robustness, given that it’s such a low number of maximum tasks, and such a fundamental & frequently used element of its operation.

Like it wouldn’t even be describable as a “rescue itself” if the response was simply “No. Too many jobs running. Please kill one to continue”

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jacquesm 3 hours ago | parent | next [-]

At that time running that many concurrent tasks on such anemic hardware was a small miracle. This wasn't your average linux kernel.

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delamon 27 minutes ago | parent | prev | next [-]

It is infinitely harder to be first. Once it is known that viable path exists, the task becomes a lot easier

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jonstewart 3 hours ago | parent | prev | next [-]

The Apollo Guidance Computer had 4KB of RAM and 16KB of ROM. Can you write a scheduler that would execute 8 programs related to landing on the moon in 4KB?

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da_chicken 2 hours ago | parent | next [-]

An asynchronous scheduler with task priority, interrupts, and real-time response. That goes on a spaceship with less than 70 Watts of power available for the computer. That weighed about 70 pounds. When there has never been that sort of a multi-tasking computer controlled avionics before.

At a time when the contemporary computer systems that used asynchronous, priority-scheduled multitasking operating systems were things like IBM OS/360 mainframes and DEC PDP-6/PDP-10 minicomputers.

It was like having an Apple II in mid 1960s with double the word size.

	▲	Gibbon1 an hour ago \| parent [-]
		I used san RTOS written in assembly for the Atmel AVR. AvrX (by John Barello) You can look at the code here. https://github.com/kororos/AvrX Compiles down under 2k. The thing is while actually doing that isn't crazy hard, they did that with hardly any existing examples to go by. And without modern tools.

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bronson 3 hours ago | parent | prev [-]

And it ran at 0.043 MIPS. Each task would get maybe 5000 instructions per second, minus scheduler overhead.

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coffeefirst 3 hours ago | parent | prev [-]

You’re forgetting this had never been done before.