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Comment by dau | Hacker News Reader

Actually no. As a programmer I do not need to know anything about exponential capacitor discarge curves and generally anything below VirtualAllocEx().

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What a silly comment.

a) “Why do we use DRAM instead of SRAM?” is a perfectly valid question from a programmer that is worth a paragraph of detail, including the capacitor discharge curves. It is not like this is a major focus of the article! It’s just a small detail in the overview of the hardware. Seems very strange to be so upset by this.

b) If you ever write software for something that isn’t a desktop or server (eg a printer, a robot, some new shiny tech) then the hardware details of RAM are absolutely relevant and can’t be abstracted away by a nice alloc API. I can understand not wanting to focus on areas like this (devices are not my cup of tea) but I can’t understand deciding it’s ipso facto irrelevant because you’re a programmer.

I think you are contorting the comment to mean something it doesn't mean. "every" is the keyword there. Not every programmer needs to know how memory works. Some programmers should know. I don't need to know for 99.99999999% of the work I do. But even that 0.00000001% it is debatable. I write code that runs on target systems. I can evaluate its performance on the target system. Now if I had to write software for a system and speed was critical and I could choose the type of memory to use, then you bet I would be reading up on this subject.

> I write code that runs on target systems. I can evaluate its performance on the target system. Now if I had to write software for a system and speed was critical and I could choose the type of memory to use, then you bet I would be reading up on this subject.

Differences between types of memory don't just matter when you're picking what hardware to purchase. It also matters greatly when trying to understand why your code achieves a certain level of performance. Understanding the characteristics of your memory matters even if you're targeting a single fixed hardware platform that you can profile your code on.

The why isn't very important. You only need to know the constraints of your system, you don't need to know why the constraints are what they are... maybe you want to, but not need.

The why does come into play, often quite unexpectedly if you don't really understand how your memory system works. I've seen StackOverflow questions about performance anomalies that could only be properly answered by digging into the details of not just cache line size, but also cache associativity.

Not understanding how the system works means that sometimes you'll have to settle for not being able to use the full performance of your hardware, and that your performance constraints will in practice be rather inscrutable and often unpredictable.

> but I can’t understand deciding it’s ipso facto irrelevant because you’re a programmer.

The negation of “everyone should know this” is not “no one should know this”. I can understand that someone would protest to a claim about how “everyone should X” by giving a blanket statement like “no I shouldn’t”, but I interpret that as hyperboly in this case.

The later parts on caches are very relevant, though.

Also, should know and need to know are slightly different, no?

All of this boils down to knowing things because you cannot look some thing up that you don't know exists, like algorithms.

https://youtu.be/rX0ItVEVjHc?t=4681

Do you just have a bookmark list of clever video comebacks to silly questions?

Perhaps they just have a decent memory?

Haha nah. This one just really resonated with me.

That depends a lot on what programming you do.

Then the word "every" is inappropriate.

"Every" Is usually tacked onto these sorts of statements by someone who either has to go around cleaning up after other people, or is just generally tired of dealing with the consequences of other people hiding behind ignorance like it's the best shield even invented.

doesn't make it right, they need therapy not lashing out with generalizations

Externalizing your problems to others isn't right either.

Being upset is one of the way we signal that social mores have been violated. Making statements about how it would be good if everyone behaves is another.

Rejecting them and saying 'not my problem' is part of the problem.

transferring specific violations to general violations is the problem in this case.

Fair point. My bad for not getting it.

As a LOB programmer who mainly puts forms over data

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