presto-main/src/main/java/io/prestosql/spiller/SpillSpaceTracker.java/SpillSpaceTracker/SpillSpaceTracker
class SpillSpaceTracker:    public SpillSpaceTracker(DataSize maxSize)
    {
        requireNonNull(maxSize, "maxSize is null");
        maxBytes = maxSize.toBytes();
        currentBytes = 0;
    }