[returningfory2]

Passing in a map would require an extra allocation for the map memory for each log line. I think the performance would probably not be great?

[packetlost]

it depends. I believe map literals are stack allocated if they aren't shared across goroutines or globals.

[masklinn]

While the hmap struct can be stack allocated if it does not escape, I’m pretty sure the buckets still need to be heap-allocated. I do not believe hmap has a “flat structure” variant which could live entirely on the stack, though I could be wrong.