---
id: SG-7
family: RT-SG
level: core
profiles: [runtime]
posture: normative-target
added: "1.0"
changed: "1.0"
source: https://flowdrop.io/spec/rules/rt-sg/sg-7
specification: FlowDrop Workflow Specification 1.0-draft
licence: CC BY 4.0
---

# SG-7 — A loop's budget counts rounds of the loop, not executions of a node

*RT-SG (Part II) · level: core · profiles: runtime · added in 1.0*

## The rule

> **Normative.** This is the rule.
>
> 1. Re-entry over a loopback edge happens only while the edge's branch is active and the loop still has budget: either its iterator has more items, or the number of rounds the loop has run is below the configured maximum.
>
> 2. That bound is per loop, keyed by the loop's head, and counts rounds rather than executions of any one node in the body.
>
> 3. The two coincide only on a body where every node runs every round; on a body with a conditional arm, a node that runs on some rounds only lags behind, and counting its executions would let the loop keep re-entering after the author's budget was spent.
>
> 4. The round counters are restored when a paused run resumes, so the bound holds across a pause.


## What it means

The budget belongs to the loop, not to any node inside it. A loop with a
conditional arm can have a node that only runs on some rounds; counting that
node's own executions would under-count the rounds actually spent, and the
loop would keep re-entering after the budget the author set was gone. The
round count is kept per loop, identified by the loop's head, precisely so a
lagging node inside it cannot buy the loop extra rounds.

That count has to survive a pause. A run paused mid-loop and resumed later
does not start the loop's counter over: the round each loop had reached is
recovered, so the same budget that would have applied without the pause
still applies after it.

## Example

A loop paused mid-run has left five jobs behind for its one loop head,
each carrying the round it was stamped with — one carrying no stamp:

```json title="The paused run's jobs, each carrying the round it ran under"
[
  {"id": 11, "metadata": {"loops": {"reason": 2}}},
  {"id": 1, "metadata": {"loops": {"reason": 0}}},
  {"id": 12, "metadata": {"loops": {"reason": 3}}},
  {"id": 2, "metadata": {"loops": {"reason": 0}}},
  {"id": 3, "metadata": {}}
]
```

```json title="What the resumed run restores the loop's round count to" verdict="restored"
{"reason": 3}
```

The job with no stamp at all contributes nothing and resets nothing.

## Related rules

- Names: SG-16, SG-17, SG-14
- Referenced by: ORC-10, SG-4, SG-10, SG-14

---

Rule identifiers are permanent and are never renumbered. This specification carries
no implementation status: each implementation publishes its own standing against
these rules. Licensed CC BY 4.0.