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420 points gnabgib | 1 comments | 15 May 25 21:57 UTC | HN request time: 0.361s | source

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drewg123 ◴[15 May 25 22:47 UTC] No.44000124[source]▶

I tend to be of the opinion that for modern general purpose CPUs in this era, such micro-optimizations are totally unnecessary because modern CPUs are so fast that instructions are almost free.

But do you know what's not free? Memory accesses[1]. So when I'm optimizing things, I focus on making things more cache friendly.

[1] http://gec.di.uminho.pt/discip/minf/ac0102/1000gap_proc-mem_...

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croes ◴[15 May 25 23:21 UTC] No.44000351[source]▶

>>44000124 #

> The world could run on older hardware if software optimization was a priority

https://news.ycombinator.com/item?id=43971464

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1. Dylan16807 ◴[16 May 25 08:22 UTC] No.44002989[source]▶

>>44000351 #

I disagree.

This is the kind of optimization that makes you need a 1.5MHz CPU instead of a 1MHz CPU, but saves devs weeks of effort. It's the kind of thing you give up when you move optimization from priority 1 to 2, or from 2 to 3. It would still run blazingly fast on a 30 year old computer. It's a perfectly good tradeoff.

The stuff that bogs down modern hardware is optimization being priority 8 or not even on the list of considerations.

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