risingwavelabs/risingwave · error · ErrorCode

Scheduler error

Error message

Scheduler error: {0}

What it means

RisingWave frontend's ErrorCode::SchedulerError variant, rendered as "Scheduler error: {0}". It wraps a BoxedError raised while scheduling a distributed query or batch task: assigning fragments/workers, scheduling on the compute nodes, or dispatching batch execution. The inner error describes the scheduling failure.

Solutions

  1. Check cluster health (SHOW NODES / cluster status) and restart any unhealthy compute nodes.
  2. Inspect frontend/compute logs around the failure for the wrapped inner error message.
  3. Verify network connectivity from the frontend node to each compute node's RPC port.
  4. Retry the query once the cluster is healthy; if persistent, check resource limits (memory) on compute nodes.
Defensive patterns

Strategy: retry

Validate before calling

// before submitting
const nodes = await showNodes(); if (nodes.filter(n => n.healthy).length === 0) throw new Error('no healthy compute nodes');

Try / catch

try { await runQuery(sql) } catch (e) {
  if (/Scheduler error/.test(e.message)) { await backoff(); retry(); }
  else throw e;
}

Prevention

When it happens

Trigger: Query scheduler fails to place a batch query on compute nodes; a compute node is unavailable or rejects task creation during query dispatch; frontend scheduler code converts an inner scheduling failure (e.g. tonic status) into ErrorCode::SchedulerError.

Common situations: Compute nodes down or OOM-killed while the frontend is up; network partition between frontend and compute nodes; cluster scaled down while queries keep arriving; resource limits preventing task creation.

Understand the failure class

Background: Database query failed: Internal Server Error 500s wrapping SQL, Prisma, and connection failures — what to check first — this error's family across 16 libraries.

Related errors


AI-assisted analysis of risingwavelabs/risingwave@6469eb736d (2026-09-11). Data as JSON: /api/errors/a34c0dfcc384bb88. Report an issue: GitHub.

Appendix: source

Thrown at src/frontend/src/error.rs:143

        #[backtrace]
        error: BoxedError,
    },
    #[error(transparent)]
    CastError(
        #[from]
        #[backtrace]
        CastError,
    ),
    #[error("Catalog error: {0}")]
    CatalogError(
        #[source]
        #[backtrace]
        #[message]
        BoxedError,
    ),
    #[error("Protocol error: {0}")]
    ProtocolError(#[message] String),
    #[error("Scheduler error: {0}")]
    SchedulerError(
        #[source]
        #[backtrace]
        BoxedError,
    ),
    #[error("Task not found")]
    TaskNotFound,
    #[error("Session not found")]
    SessionNotFound,
    #[error("Invalid reference: {0}")]
    InvalidReference(String),
    #[error("Item not found: {0}")]
    ItemNotFound(String),
    #[error("Duplicate Relation Name: {0}")]
    DuplicateRelationName(String),
    #[error("Invalid insert operation: {0}")]
    InsertViolation(String),
    #[error("Invalid input syntax: {0}")]

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