Task schedule fail event

This event is emitted when a task failed to be scheduled and will be retried later. This is a temporary failure at task scheduling time due to resource limitation, for example not enough slots available on nodes to run a task with requiredSlots specified.

The following example shows the body of a task schedule fail event.

{
    "jobId": "job-01",
    "id": "task-01",
    "taskType": "User",
    "systemTaskVersion": 665378862,
    "requiredSlots": 1,
    "nodeInfo": {
        "poolId": "pool-01",
        "nodeId": " "
    },
    "multiInstanceSettings": {
        "numberOfInstances": 1
    },
    "constraints": {
        "maxTaskRetryCount": 0
    },
    "schedulingError": {
        "category": "UserError",
        "code": "JobPreparationTaskFailed",
        "message": "Task cannot run because the job preparation task failed on node"
    }
}

Element name	Type	Notes
jobId	String	The ID of the job containing the task.
id	String	The ID of the task.
taskType	String	The type of the task. This can either be 'JobManager' indicating it is a job manager task or 'User' indicating it is not a job manager task. This event is not emitted for job preparation tasks, job release tasks or start tasks.
systemTaskVersion	Int32	This is the internal retry counter on a task. Internally the Batch service can retry a task to account for transient issues. These issues can include internal scheduling errors or attempts to recover from compute nodes in a bad state.
requiredSlots	Int32	The required slots to run the task.
nodeInfo	Complex Type	Contains information about the compute node on which the task ran.
multiInstanceSettings	Complex Type	Specifies that the task is a Multi-Instance Task requiring multiple compute nodes. See multiInstanceSettings for details.
constraints	Complex Type	The execution constraints that apply to this task.
schedulingError	Complex Type	Contains information about the scheduling error of the task.

nodeInfo

Element name	Type	Notes
poolId	String	The ID of the pool on which the task ran.
nodeId	String	The ID of the node on which the task ran.

multiInstanceSettings

Element name	Type	Notes
numberOfInstances	Int32	The number of compute nodes required by the task.

constraints

Element name	Type	Notes
maxTaskRetryCount	Int32	The maximum number of times the task may be retried. The Batch service retries a task if its exit code is nonzero. Note that this value specifically controls the number of retries. The Batch service will try the task once, and may then retry up to this limit. For example, if the maximum retry count is 3, Batch tries a task up to 4 times (one initial try and 3 retries). If the maximum retry count is 0, the Batch service does not retry tasks. If the maximum retry count is -1, the Batch service retries tasks without limit. The default value is 0 (no retries).

schedulingError

Element name	Type	Notes
category	String	The category of the error.
code	String	An identifier for the task scheduling error. Codes are invariant and are intended to be consumed programmatically.
message	String	A message describing the task scheduling error, intended to be suitable for display in a user interface.