presto-main/src/main/java/io/prestosql/operator/aggregation/histogram/SingleHistogramState.java/SingleHistogramState/getEstimatedSize
class SingleHistogramState:    @Override
    public long getEstimatedSize()
    {
        long estimatedSize = INSTANCE_SIZE;

        if (typedHistogram != null) {
            estimatedSize += typedHistogram.getEstimatedSize();
        }
        return estimatedSize;
    }