private void removeFromCache(BufferNode node) {
		if (node.buffer != null) {
			node.removeFromCache();
			node.buffer = null;

			--buffersOnHand;
			if (buffersOnHand < lowWaterMark) {
				lowWaterMark = buffersOnHand;
			}
		}
	}
Remove a buffer node from memory cache.
@param node buffer node
Ghidra/Framework/DB/src/main/java/db/buffers/BufferMgr.java