View a markdown version of this page

CHUNK[INT] task parameter reference - Deadline Cloud

CHUNK[INT] task parameter reference

The CHUNK[INT] task parameter type defines an integer task parameter that Deadline Cloud processes as chunks instead of as individual values. A chunked task parameter has the following structure:

taskParameterDefinitions:
  - name: identifier
    type: CHUNK[INT]
    range: integer range expression
    chunks:
      defaultTaskCount: integer
      rangeConstraint: CONTIGUOUS | NONCONTIGUOUS
      targetRuntimeSeconds: integer

The following table describes each field.

Field Required Description
range Yes The full set of integer values to process, as a list of integers or an integer range expression such as "1-100" or "1,3,7-20:2". Accepts a job parameter reference such as "{{Param.Frames}}".
chunks.defaultTaskCount Yes The number of values to combine into a single chunk. The maximum value is 150. Accepts a job parameter reference such as "{{Param.ChunkSize}}".
chunks.rangeConstraint Yes The shape of each chunk. With CONTIGUOUS, every chunk is a consecutive range such as 1-10. With NONCONTIGUOUS, a chunk can be an arbitrary set such as 1,3,7-10.
chunks.targetRuntimeSeconds No The target runtime for each chunk, in seconds. When set, Deadline Cloud adjusts chunk sizes toward the target based on the observed runtimes of completed chunks. When not set, every chunk uses defaultTaskCount values.

The CHUNK[INT] type has the following constraints:

  • The job template must list TASK_CHUNKING in its extensions. Without the extension, job creation fails with the error The CHUNK[INT] task parameter requires the TASK_CHUNKING extension.

  • A step's parameter space can contain at most one CHUNK[INT] parameter. When a chunk runs, all other task parameters take on a single value while the chunked parameter takes a set of values.

In a step's script, the {{Task.Param.name}} variable for a chunked parameter expands to an integer range expression string. With rangeConstraint: CONTIGUOUS, the expression is always in start-end format, such as 1-1 or 11-20. With rangeConstraint: NONCONTIGUOUS, the expression can be any integer range expression, such as 1-3,5,7-20:2.

For more information, see the following resources: