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Go channels are bad

(www.jtolds.com)
298 points jtolds | 1 comments | | HN request time: 0.001s | source
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sagichmal ◴[] No.11211112[source]
This is a frustrating and overly-exasperated post which reaches conclusions that have always been part of the Go canon. APIs should be designed synchronously, and the callers should orchestrate concurrency if they choose -- yes! Channels are useful in some circumstances, but if you just want to synchronize access to shared memory (like the author's example) then you should just use a mutex -- yes! These are well understood truths.

Novices to the language have a tendency to overuse channels. Here is Andrew Gerrand addressing precisely this point two years ago at GopherCon: https://www.youtube.com/watch?v=u-kkf76TDHE&t=815

Neither the referenced performance characteristics via Tyler Treat, nor the FUD surrounding channel-based program architecture, invalidate channels generally. One does have to think carefully about ownership hierarchies: only one goroutine gets to close the channel. And if it's in a hot loop, a channel will always perform worse than a mutex: channels use mutexes internally. But plenty of problems are solved very elegantly with channel-based CSP-style message passing.

It's unfortunate that articles like this are written and gain traction. The explicit instruction to [new] Go programmers is that they should avoid channels, even that they are badly implemented, and both of those things are false.

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1. admiun ◴[] No.11211656[source]
"APIs should be designed synchronously, and the callers should orchestrate concurrency if they choose"

Just to add to this, I found the blog post he mentions[1] towards the bottom that supports this conclusion a really good read.

[1] http://journal.stuffwithstuff.com/2015/02/01/what-color-is-y...