Show HN: A pure reference counting GC in Go

Re:Show HN: A pure reference counting GC in Go by cesarb on Wednesday January 15, 2020 @05:50AM (#22053209)

> Additionally, if there is a big data structure in use, reaching zero will trigger a cascade deletion events reaching stop-the-world like effect.

Even a deletion cascade won't stop the world: only the single thread which reached zero will be "stopped". While in tracing GC, a "stop-the-world" stops all threads, even the ones which aren't doing any allocation or deallocation at the moment.

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Re:Show HN: A pure reference counting GC in Go by zozbot234 on Wednesday January 15, 2020 @06:07AM (#22053274)

There are concurrent GC's that don't pause all threads while running garbage collection. Plus the whole point of GC is that it's what you use when you just don't know at runtime which operations should involve "allocation or deallocation" of objects. From the POV of tracing GC, any "new" reference to an object might be the reference that extends its lifetime and prevents it being collected, and conversely when removing a reference.

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Re:Show HN: A pure reference counting GC in Go by imtringued on Wednesday January 15, 2020 @06:41AM (#22053404)

Those GCs are special exceptions. Most modern GCs just aim to have bearably low pause times.

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Re:Show HN: A pure reference counting GC in Go by pjmlp on Wednesday January 15, 2020 @06:54AM (#22053468)

High performance tracing GC algorithms don't stop all threads.

Also there are tracing GC that operate with local heaps.

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