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Comment by nottorp | Hacker News Reader

I have a feeling that a naive implementation in Java would be a lot worse than a naive implementation in Go so optimizing matters more there.

Had to parse csvs in Java on a very memory constrained system once... we ended up cutting out a feature because it wasn't worth it.

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Depends what you call “naive”, but the “idiomatic Java solution” from last week’s post (https://questdb.io/blog/billion-row-challenge-step-by-step/) clocked in at 71 seconds, or 1:11. And just running it on graal was down to 66.

“Very memory constrained” would be a massive factor here, 1BRC is not really constrained (let alone very much so), it has 1 billion rows on a 32GB machine.

Gigabytes? It was a while ago and i had megabytes for the whole OS :)

Anyway, it's just a fun memory now.

Depends on which Java implementation is used.

People keep forgetting Java is like C and C++, plenty of implementations to choose from, each with its own approach to JIT, AOT, GC and escape analysis.

For what it's worth, on my machine the simple/idiomatic "baseline" Java solution (https://github.com/gunnarmorling/1brc/blob/main/src/main/jav...) takes 2m0s, compared to 1m45s for my simple Go version. So Go is a bit better for the naive version.

Regarding Java, It probably could be done with arrays and object reuse (arenas). But it's slightly less ergonomic. And the ecosystem isn't designed for it, so you'd have to implement your own memory-efficient parser.

Yep, but it wasn't a critical feature and we were in a rush, so the feature was killed instead.

> Depends on which Java implementation is used.

... if you have a choice. It was a port of AOSP, so we didn't. In any case it wasn't the jvm's fault, the device just had very little ram.

Sounds like a skill issue

Golang is actually not as efficient as Java in quite a few benchmarks.

~~Using LLVM isn’t a magic solution to perform better than something relying on the JVM.~~

Here is a source: https://sites.google.com/view/energy-efficiency-languages

Huh? Go doesn't use LLVM though, where did you get the idea that it does? That's part of why its compile times are so fast.

You are right, it doesn’t use LLVM. No idea where I got the idea, I was confidently wrong.

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