alt Hacker NewsIsn't a dedicated worker pool with priority queues enough to get predictable P99 without leaving Go?
If you fix N workers and control dispatch order yourself, the scheduler barely gets involved — no stealing, no surprises.
The inter-goroutine handoff is ~50-100ns anyway.
Isn't the real issue using `go f()` per request rather than something in the language itself?
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withinboredom • today at 9:56 AM
No. Eventually the queues get full and go routines pause waiting to place the element onto the queue, landing you right back at unfair scheduling.
https://github.com/php/frankenphp/pull/2016 if you want to see a “correctly behaving” implementation that becomes 100% cpu usage under contention.
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My usecase was building an append-only blob store with mandatory encryption, but using a semaphore + direct goroutine calls to limit background write concurrency instead of a channel + dedicated writer goroutines was a net win across a wide variety of write sizes and max concurrent inflight writes. It is interesting that frankenphp + caddy came up with almost the same conclusion despite vastly different work being done.