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Go channels are bad

(www.jtolds.com)
298 points jtolds | 2 comments | 02 Mar 16 15:40 UTC | HN request time: 0.536s | source
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Jabbles ◴[02 Mar 16 16:02 UTC] No.11210740[source]▶
Effective Go has always said:

Do not communicate by sharing memory; instead, share memory by communicating.

This approach can be taken too far. Reference counts may be best done by putting a mutex around an integer variable, for instance.

https://golang.org/doc/effective_go.html#sharing

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poizan42 ◴[02 Mar 16 16:19 UTC] No.11210862[source]▶
Reference counts are best done using interlocked increment/decrement primitives.
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chrisseaton ◴[02 Mar 16 16:47 UTC] No.11211088[source]▶
I wonder if there are any compilers which can replace

    mutex.lock { x++ }
With a 'lock xaddl x 1' instruction.
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1. mike_hearn ◴[02 Mar 16 18:05 UTC] No.11211703[source]▶
It's not quite the same thing but recent JVMs can translate synchronised blocks into Intel TSX transactions, which means multiple threads can run inside the lock at once, with rollback and retry if interference is detected at the hardware (cache line) level. So yeah .... almost. But it's fancy and cutting edge stuff.
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2. ◴[02 Mar 16 18:06 UTC] No.11211715[source]▶