prestodb/presto · error · IllegalArgumentException

Query Prerequisites '%s' is already registered

Error message

Query Prerequisites '%s' is already registered

What it means

ConfidenceBasedClusterTtlProviderManager.addClusterTtlProviderFactory throws IllegalArgumentException when a ClusterTtlProviderFactory whose getName() is already present in the clusterTtlProviderFactories map is registered again (putIfAbsent returns non-null). Factory names must be unique within the manager.

Source

Thrown at presto-main-base/src/main/java/com/facebook/presto/ttl/clusterttlprovidermanagers/ConfidenceBasedClusterTtlProviderManager.java:68

    @Inject
    public ConfidenceBasedClusterTtlProviderManager(NodeTtlFetcherManager nodeTtlFetcherManager)
    {
        this.nodeTtlFetcherManager = requireNonNull(nodeTtlFetcherManager, "nodeTtlFetcherManager is null");
    }

    @Override
    public ConfidenceBasedTtlInfo getClusterTtl()
    {
        return clusterTtlProvider.get().getClusterTtl(ImmutableList.copyOf(nodeTtlFetcherManager.getAllTtls().values()));
    }

    @Override
    public void addClusterTtlProviderFactory(ClusterTtlProviderFactory clusterTtlProviderFactory)
    {
        requireNonNull(clusterTtlProviderFactory, "clusterTtlProviderFactory is null");
        if (clusterTtlProviderFactories.putIfAbsent(clusterTtlProviderFactory.getName(), clusterTtlProviderFactory) != null) {
            throw new IllegalArgumentException(format("Query Prerequisites '%s' is already registered", clusterTtlProviderFactory.getName()));
        }
    }

    @Override
    public void loadClusterTtlProvider()
            throws Exception
    {
        if (Files.exists(CLUSTER_TTL_PROVIDER_CONFIG)) {
            Map<String, String> properties = new HashMap<>(loadProperties(CLUSTER_TTL_PROVIDER_CONFIG.toFile()));
            String factoryName = properties.remove(CLUSTER_TTL_PROVIDER_PROPERTY_NAME);

            checkArgument(!isNullOrEmpty(factoryName),
                    "Cluster Ttl Provider configuration %s does not contain %s", CLUSTER_TTL_PROVIDER_CONFIG.toAbsolutePath(), CLUSTER_TTL_PROVIDER_PROPERTY_NAME);
            load(factoryName, properties);
        }
        else {
            load("infinite", ImmutableMap.of());
        }

View on GitHub (pinned to 55bb57d202)

Solutions

1. Remove duplicate plugin jars so the factory is only loaded once.
2. Rename one factory's getName() to a unique value.
3. Guard registration: check clusterTtlProviderFactories contains the name before adding.
4. Create a fresh manager instance per test/setup instead of reusing it.

Example fix

// before
manager.addClusterTtlProviderFactory(new MyTtlProviderFactory("confidence"));
manager.addClusterTtlProviderFactory(new OtherFactory("confidence")); // duplicate

// after
String name = "my-unique-ttl-provider";
if (manager.getClusterTtlProviderFactories().stream().noneMatch(f -> f.getName().equals(name))) {
    manager.addClusterTtlProviderFactory(new MyTtlProviderFactory(name));
}

// Check for existing factory with same name before registering
boolean exists = manager.getClusterTtlProviderFactories().stream()
    .anyMatch(f -> f.getName().equals(newFactory.getName()));
if (exists) {
    // skip registration or fail with a clear duplicate error
}

boolean isFactoryNameFree(ClusterTtlProviderManager m, String name) {
    return m.getClusterTtlProviderFactories().stream().noneMatch(f -> f.getName().equals(name));
}

try {
    manager.addClusterTtlProviderFactory(factory);
} catch (IllegalArgumentException e) {
    LOG.warn("TTL provider factory '%s' already registered; ignoring duplicate", factory.getName());
}

When it happens

Trigger: Calling addClusterTtlProviderFactory twice with factories sharing the same name — typically re-running plugin setup, loading two plugin versions that both register the same TTL provider factory name, or a plugin registering a name that collides with a built-in factory.

Common situations: See trigger scenarios.

Related errors

• Node ttl fetcher factory '%s' is already registered
• NODE_SELECTION_NOT_SUPPORTED
• NO_NODES_AVAILABLE
• ALREADY_EXISTS
• FUNCTION_IMPLEMENTATION_MISSING

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/af6ed2641da89471. Report an issue: GitHub.