I actually wrote a Rust version as well, and yes, it was far easier to write, far less code (although not incorporating all the tricks), completely safe, and pretty fast -- but still 2x slower than my end result in Java.
HashMap was quite a bottleneck in Rust as well, for many reasons, not just the key allocation problem. But it was very easy to implement the same kind of custom hashtable, which almost by default ends up having a better memory layout than in Java.
HashMap was quite a bottleneck in Rust as well, for many reasons, not just the key allocation problem. But it was very easy to implement the same kind of custom hashtable, which almost by default ends up having a better memory layout than in Java.
https://github.com/mtopolnik/rust-1brc/blob/main/src/main.rs
I bet I could improve on it just a bit and match the Java time. Not sure about topping it, though.