INORDINATE AMOUNT OF TIME


ISSUE:
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While serializing a json array, the number of allocs is
very high. This is because of the number of times
String::append is called, which in turn calls
String::mem_realloc. The allocation for the buffer happens
linearly and takes significant time.

SOLUTION:
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The solution is to allocate larger chunks for the buffer
and reduce the total number of allocs.

The fix is a backport of Bug#22239803.