EsqlActionBreakerIT fails in a number of different ways. This issue intends to be a place to capture such failures, so that they can be analysed and worked on separately. 
x-pack/plugin/esql/compute/src/main/java/org/elasticsearch/compute/operator/OrdinalsGroupingOperator.java
public void finish() {
        finished = true;
        if (valuesAggregator != null) {
            valuesAggregator.finish();
        }
    }
    private Page mergeOrdinalsSegmentResults() throws IOException {
        
        final PriorityQueue<AggregatedResultIterator> pq = new PriorityQueue<>(ordinalAggregators.size()) {
            @Override
            protected boolean lessThan(AggregatedResultIterator a, AggregatedResultIterator b) {
                return a.currentTerm.compareTo(b.currentTerm) < 0;
            }
        };
        final List<GroupingAggregator> aggregators = createGroupingAggregators();
        try {
            boolean seenNulls = false;
            for (OrdinalSegmentAggregator agg : ordinalAggregators.values()) {
                if (agg.seenNulls()) {
                    seenNulls = true;
                    for (int i = 0; i < aggregators.size(); i++) {
                        aggregators.get(i).addIntermediateRow(0, agg.aggregators.get(i), 0);
                    }
                }
            }
            for (OrdinalSegmentAggregator agg : ordinalAggregators.values()) {
                final AggregatedResultIterator it = agg.getResultIterator();
                if (it.next()) {
                    pq.add(it);
                }