Bulk queue window math: 8 gift clips at concurrency 3

A Sume bulk queue with 8 items and concurrency: 3 answers the create call with three items running and five queued. Each time one item reaches a terminal state, the next queued item starts, so three stay in flight until fewer than three items remain.

This is the window rule in Bulk runs (read 2026-10-06). Use it to pick a concurrency for a holiday batch, since the number decides how many clips Sume works on at once, and it must stay between 1 and 16.

How does the window move?

The table follows 8 gift clips at concurrency: 3. Terminal states are completed, failed, and canceled, and each of them frees a slot.

Why does a failed item not stop the queue?

A failed item is terminal and frees its slot, so the next item starts. If a child cannot start at all, that item becomes failed with run_id: null and an error, while the queue create had already returned 202 and the rest continue.

• The window never goes above concurrency, even if you poll more than once.
• Child runs still pass ordinary Format-run admission: wallet, workspace generation concurrency, and spend caps. A small workspace limit can make a high concurrency mostly wait.
• A canceled child frees its slot the same way as a finished one.

How do I pick the number?

Start with the number of clips you want to review at a time. A larger window finishes the batch sooner, but a failed prompt is then repeated more times before you notice, so test a concurrency of 1 on item 0 first if the Format is new to you.