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ZGC is not available on a 32 bit Java, and always uses 64 bit pointers, so there is no advantage to setting the heap size below 32GB, as there is with G1 and older collectors.
ZGC claims that its pause times do NOT increase as the heap gets larger. Older collectors like Parallel, CMS, and G1 do show an increase in pause times as the heap grows.
CMS (ConcurrentMarkSweep) Collector
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