prestodb/presto · error · PrestoException

NODE_SELECTION_NOT_SUPPORTED

NODE_SELECTION_NOT_SUPPORTED

Error message

Unsupported node selection strategy %s

What it means

Defensive default branch in SimpleNodeSelector.computeAssignments: the split's NodeSelectionStrategy is not one of the recognized values (HARD_AFFINITY, SOFT_AFFINITY, NO_AFFINITY), so no node-selection code path exists for it.

Source

Thrown at presto-main-base/src/main/java/com/facebook/presto/execution/scheduler/nodeSelection/SimpleNodeSelector.java:187

            List<InternalNode> candidateNodes;
            switch (split.getNodeSelectionStrategy()) {
                case HARD_AFFINITY:
                    candidateNodes = selectExactNodes(nodeMap, split.getPreferredNodes(nodeProvider), includeCoordinator);
                    preferredNodeCount = OptionalInt.of(candidateNodes.size());
                    break;
                case SOFT_AFFINITY:
                    candidateNodes = selectExactNodes(nodeMap, split.getPreferredNodes(nodeProvider), includeCoordinator);
                    preferredNodeCount = OptionalInt.of(candidateNodes.size());
                    candidateNodes = ImmutableList.<InternalNode>builder()
                            .addAll(candidateNodes)
                            .addAll(randomNodeSelection.pickNodes(split))
                            .build();
                    break;
                case NO_PREFERENCE:
                    candidateNodes = randomNodeSelection.pickNodes(split);
                    break;
                default:
                    throw new PrestoException(NODE_SELECTION_NOT_SUPPORTED, format("Unsupported node selection strategy %s", split.getNodeSelectionStrategy()));
            }

            if (candidateNodes.isEmpty()) {
                log.debug("No nodes available to schedule %s. Available nodes %s", split, nodeMap.getActiveNodes());
                throw new PrestoException(NO_NODES_AVAILABLE, "No nodes available to run query");
            }

            SplitWeight splitWeight = split.getSplitWeight();
            Optional<InternalNodeInfo> chosenNodeInfo = Optional.empty();

            if (taskLoadSplitWeightProvider.isPresent()) {
                chosenNodeInfo = chooseLeastBusyNode(splitWeight, candidateNodes, taskLoadSplitWeightProvider.get(), preferredNodeCount, maxSplitsWeightPerTask, assignmentStats);
            }
            else {
                chosenNodeInfo = chooseLeastBusyNode(splitWeight, candidateNodes, assignmentStats::getTotalSplitsWeight, preferredNodeCount, maxSplitsWeightPerNode, assignmentStats);
                if (!chosenNodeInfo.isPresent()) {
                    chosenNodeInfo = chooseLeastBusyNode(splitWeight, candidateNodes, assignmentStats::getQueuedSplitsWeightForStage, preferredNodeCount, maxPendingSplitsWeightPerTask, assignmentStats);
                }

View on GitHub (pinned to 55bb57d202)

Solutions

1. Fix the connector split manager to return one of the supported NodeSelectionStrategy values
2. Update Presto to a version whose scheduler knows the newer strategy value
3. Avoid the connector version/feature combination that emits the unknown strategy

When it happens

Trigger: Thrown at presto-main-base/src/main/java/com/facebook/presto/execution/scheduler/nodeSelection/SimpleNodeSelector.java:187 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/259440214003b19e. Report an issue: GitHub.