private static ResultMetrics getResult(List<Future<ResultMetrics>> futureResults) {
        try {
            ResultMetrics combined = futureResults.get(0).get();
            for (int i = 1; i < futureResults.size(); i++) {
                combined.combine(futureResults.get(i).get());
            }
            return combined;
        } catch (InterruptedException | ExecutionException e) {
            throw new RuntimeException(e);
        }
    }
A benchmark that tests the indexing and search performance.

@author bjorncs
predicate-search/src/main/java/com/yahoo/search/predicate/benchmarks/PredicateIndexBenchmark.java