The big win here is having a GC by default, with the ability to reduce heap allocations (via stack) just by adding in more typing annotations.
Switching to OxCaml with exclave_ stack_ annotations drops
p99.9 latency from 29 ns to 9 ns per packet on the dispatch
hot path, and removes GC pressure entirely (394 minor GCs to
zero over 25 million packets). Throughput is comparable [...]
I got a similar result with my 'httpz' stack a few months ago (https://anil.recoil.org/notes/oxcaml-httpz) which my website's been running on without drama. And, I gotta say, OxCaml's a surprisingly robust compiler for being packed full of bleeding edge extensions: not a single crash on my infra is attributable to a compiler bug (plenty of bad OCaml code, but not due to a compilation bug)
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