[vitpro2213]

If you discard the old array (and allocate a bigger one before), you must also copy all enqueued material.

Also this one enqueue will be mega expensive - a clear "fat tail" in the latency histogram.

In MultiArrayQueue you keep all already enqueued material in-place, "just" allocate the bigger array, register the new diversion, enqueue the one new element - and done.

Thanks

[Szpadel]

why not free previous smaller chunk after reader finished reading from it?

for me it would be better to allocate new buffer but allow reading from old one until it contains data and after that dealocate it and keep only new one in use

[zamalek]

You might run into ABA, though that isn't an issue for managed languages.

[jauntywundrkind]

Yeah, leaving small old buffers behind seems like a major no-no to me. It could be useful if you think you'll shrink back down, but it feels like cache locality suffering and iteration/tracking penalties strongly incentive getting rid of the old buffer asap.

One other thing I want to shout out, I saw what I thought was a really neat multicast ring buffer the other day where the author has an atomic for each element, rather than the typical reader/writer atomics. The promise was having much less contention on any given atomic, in most cases. https://github.com/rezabrizi/SPMC-Queue https://news.ycombinator.com/item?id=40410172