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Scala 3 slowed us down?

(kmaliszewski9.github.io)
261 points kmaliszewski | 3 comments | 07 Dec 25 15:08 UTC | HN request time: 0.001s | source
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munchler ◴[07 Dec 25 17:34 UTC] No.46183417[source]▶
I’m not familiar with Scala’s macro system, but it seems like a big takeaway here is: Be careful with code that invokes the compiler (JIT) at runtime. That seems like it’s asking for trouble.
replies(1): >>46183886 #
dtech ◴[07 Dec 25 18:34 UTC] No.46183886[source]▶
Macro's are compile time, there is no runtime codegen.

The problem was overly-frequent inlining generating enormous expressions, causing a lot JIT phase and slow execution.

replies(2): >>46183957 #>>46185245 #
1. gavinray ◴[07 Dec 25 21:17 UTC] No.46185245[source]▶
That's not true, Spark's entire query engine relies on use of runtime codegen via macros/quasi quotes

Look up the architecture of Catalyst + Tungsten

https://www.databricks.com/glossary/catalyst-optimizer

replies(2): >>46187183 #>>46211270 #
2. lmm ◴[08 Dec 25 01:10 UTC] No.46187183[source]▶
Catalyst uses runtime codegen, sure, but the OP wasn't using that.
3. still_grokking ◴[09 Dec 25 21:55 UTC] No.46211270[source]▶
Scala 2's macros are compile time constructs. There is no runtime code generation / staging.

Scala 3's macros support staged compilation, so you can have macros which create code in later stages at runtime.

https://docs.scala-lang.org/scala3/reference/metaprogramming...