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Ergo: Erlang-inspired event driven actor framework in Go

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175 points nateb2022 | 6 comments | 12 Sep 24 11:06 UTC | HN request time: 0.001s | source | bottom
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nahuel0x ◴[12 Sep 24 16:56 UTC] No.41522944[source]▶
Three big differences in comparison with Erlang: 1- Cannot externally kill a process (yes, ergo process have a Kill method but the process will be in a "zombie" state until the current message handlers returns... maybe stuck forever) 2- No hot code reloading. 3- No per-process GC.
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throwaway894345 ◴[12 Sep 24 17:50 UTC] No.41523543[source]▶
I've never written any Erlang before--why do I care about per-process GC?
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1. victorbjorklund ◴[12 Sep 24 18:21 UTC] No.41523906[source]▶
More consistent performance. No stopping the whole world.
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2. throwaway894345 ◴[12 Sep 24 19:32 UTC] No.41524621[source]▶
That makes sense. I wonder how important this is versus Go, considering Go has a sub-millisecond GC even without per-process GC? (Go also makes much more use of the stack which might be sort of analogous to per-process GC?)
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3. weatherlight ◴[12 Sep 24 20:31 UTC] No.41525191[source]▶
This can cause GC to become "bursty."

BeamVM languages complete side step this problem all together.

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4. hosh ◴[13 Sep 24 00:07 UTC] No.41526951{3}[source]▶
Out in the field, smoothing out variances can be just as important to overall performance and reliability.
5. pdimitar ◴[13 Sep 24 08:10 UTC] No.41529072[source]▶
I have some production experience with Golang and one thing that helps it emulate Erlang's BEAM VM (also used by Elixir, FYI) is to have the goroutines be short-lived and/or disposable. No need for persistent workers most of the time anyway unless you are chasing every last millisecond of performance -- in those cases persistent workers waiting to snatch a job definitely perform better (though only by something like 1-2% in my limited experience; but that can be still a lot depending on hosting and workloads and customer expectations f.ex. in finance forgoing 1-2% perf is almost criminal).

So the BEAM VM definitely handles things a bit better but Golang can get quite close.

6. throwaway894345 ◴[13 Sep 24 16:44 UTC] No.41532876{3}[source]▶
What specifically causes GC to become bursty? Presumably a low latency GC is not "bursty" more or less by definition?