max heap        : 512 MB
target live set : 281 MB (55% of heap)
threads         : 12, duration: 20 s

filling live set ...
live set filled: 4,505 chunks x 64 KB
now allocating hard for 20 s -- expect stalls

allocation phase done

========================================================================
JFR summary  (C:\Users\Ankur\allocation-stalls.jfr)
========================================================================
young collections : 0
old collections   : 0
page allocations  : 0
ALLOCATION STALLS : 0

No stalls recorded. Either the heap was big enough, or you are not
running ZGC. Shrink -Xmx or raise -Dseconds and try again.