Transloadit

What is a Job Slot Limit?

A Job Slot Limit is the concurrency allowance that comes with a Transloadit subscription plan and applies per Workspace in each processing region. Priority Job Slots bound how many weighted Encoding Jobs can run in the Live Queue at once, and a separate batch job slot allowance bounds concurrent batch work; live jobs beyond the priority allowance wait in a Backup Queue until slots free up.

How Job Slot Limits work

The limit is a weighted concurrency budget rather than a simple count of files or Assemblies. Each active job claims a Robot-specific number of slots; for example, an image resize claims 5 and a video encode claims 60. The total is evaluated for the Workspace within each processing region. Overflow beyond the priority allowance waits in a Backup Queue and retains its intended queue, which is different from deliberately assigning a Step to the Batch Queue. Planning therefore uses the mix and duration of operations, not upload volume alone.

Key facts

  1. Robot types have different slot claims, so the same limit can admit many lightweight image operations but far fewer simultaneous video encodes.
  2. Priority and batch job slot allowances apply per processing region, so traffic distribution across regions can change observed concurrency without any plan change.
  3. Exceeding the limit does not fail jobs: excess live work trickles into a Backup Queue and is re-enqueued to the Live Queue as the Workspace’s slots free up, while a step-level queue setting can intentionally send nonurgent work to the shared Batch Queue.

When Job Slot Limits matter

Plan capacity around the slot costs of the Robots you use and the latency your urgent work requires. When live jobs exceed the Priority Job Slots, the excess waits in a Backup Queue and returns to the Live Queue as running jobs complete; higher or custom limits come from upgrading the plan or arranging an add-on with support rather than from a settings page.

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