public static int getSize(long memAddr) {
    MemoryAllocatorImpl.validateAddress(memAddr);
    return AddressableMemoryManager.readInt(memAddr + CHUNK_SIZE_OFFSET);
  }
Validates that the fill pattern for this chunk has not been disturbed. This method assumes the
TINY_MULTIPLE is 8 bytes.

@throws IllegalStateException when the pattern has been violated.
geode-core/src/main/java/org/apache/geode/internal/offheap/OffHeapStoredObject.java