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If a JVM is started with unequal initial and max heap size, it can be
prone to pauses as the JVM heap is resized during system usage. To avoid
these resize pauses, it’s best to start the JVM with the initial heap
size equal to the maximum heap size. Additionally, if
bootstrap.memory_lock is enabled, the JVM will
lock the initial size of the heap on startup. If the initial heap size
is not equal to the maximum heap size, after a resize it will not be the
case that all of the JVM heap is locked in memory. To pass the heap size
check, you must configure the heap size.