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Comment by withinboredom

18 days ago

This is pretty easy to refute:

> If your program runs in O(n) time, it cannot use more than O(n) memory (upper bound on memory usage.[sic]

This is clearly refuted by all software running today. Programs (especially games) clearly use more memory than there are instructions in the program.

> If your program uses O(n) memory, it must run at least in O(n) time (lower bound on time).

Memory bombs use an incredible amount of memory and do it incredibly quickly.

>Programs (especially games) clearly use more memory than there are instructions in the program.

How can you access a piece of memory without issuing an instruction to the CPU? Also, "clearly" is not an argument.

>Memory bombs use an incredible amount of memory and do it incredibly quickly.

How can you access a piece of memory without issuing an instruction to the CPU? Also "incredibly quickly" is not an argument. Also also, O(n) is incredibly quick.

  • > Also, "clearly" is not an argument.

    As in your assertion is literally self-evidently false. It is on you to provide a burden of proof here; especially since there are instructions that can load more than a single bit of memory.

    > How can you access a piece of memory without issuing an instruction to the CPU?

    Let me rather ask you this: where do the instructions exist that are running? That is right: in memory. However, just because instructions exist in memory doesn’t mean they’re accessed. There is not a relationship between the number of instructions and the amount of memory accessed/used.

    • This is about time and memory complexity, which is a formal field of computer science. Your replies are about your own vague understanding of computing, which is not the topic here.

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