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WebSockets cost us $1M on our AWS bill

(www.recall.ai)
257 points tosh | 2 comments | 06 Nov 24 18:50 UTC | HN request time: 0.418s | source
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cperciva ◴[06 Nov 24 21:20 UTC] No.42069585[source]▶
We use atomic operations to update the pointers in a thread-safe manner

Are you sure about that? Atomics are not locks, and not all systems have strong memory ordering.

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1. jpc0 ◴[06 Nov 24 21:58 UTC] No.42070126[source]▶
> ... update the pointers ...

Pretty sure ARM and x86 you would be seeing on AWS does have strong memory ordering, and has atomic operations that operate on something the size of a single register...

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2. cperciva ◴[06 Nov 24 22:09 UTC] No.42070251[source]▶
Graviton has weaker memory ordering than amd64. I know this because FreeBSD had a ring buffer which was buggy on Graviton...