fix(pb): remove actor sleep ts when allocated

[MasterPtato]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[MasterPtato]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• fix(pb-envoy): hard abort ws to tunnel on ping error #4776
• fix(outbound): implement drain grace period #4775
• fix(pb): fix pool config defaults #4774
• fix(pb): remove actor sleep ts when allocated #4772 👈 (View in Graphite)
• refactor(gateway): clean up and fix lost tunnel msgs #4771
• refactor(pb): fix actor overdue alarm handling #4770
• fix: update railway docs to include graceful shutdown #4715
• fix: add wf registry command #4714
• chore: move code #4713
• fix(gas): add large txn retries for pulling signals, tighten commit interval for actors #4712
• fix: improve epoxy propose errors, add gcp logging fmt #4698
• fix: autogenerate bare protocol versions #4696
• main

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[claude]

Code Review: fix(pb): remove actor sleep ts when allocated (#4772)

File: engine/packages/pegboard/src/workflows/actor2/runtime.rs

Summary

This PR fixes a real bug in the allocate activity in actor2/runtime.rs. Previously, SleepTsKey was deleted unconditionally at the start of every allocation attempt — even when the allocation failed (e.g., due to ConcurrentActorLimitReached or NoEnvoys). Now the deletion is gated on a successful allocation (allocation.is_some()). The fix is correct and minimal.

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What the Bug Was

Before this change, the following was placed unconditionally inside the FDB transaction before any allocation decision was made:

// Set not sleeping
tx.delete(&keys::actor::SleepTsKey::new(actor_id));

This meant that a sleeping actor that failed to allocate (no envoys available, concurrent actor limit reached) would have its SleepTsKey deleted and state.sleep_ts cleared — even though the actor remained in a sleeping/reallocating state. This could cause the gateway (ops/actor/get_for_gateway.rs) to report sleeping: false for an actor that was actually still sleeping, potentially preventing proper wake-on-request behavior.

After the fix, tx.delete and state.sleep_ts = None are only executed when allocation.is_some().

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Correctness Analysis

The fix is logically sound. The set_sleeping activity writes SleepTsKey and sets state.sleep_ts = Some(now). The only correct time to clear them is when the actor is actually being woken up, which requires a successful allocation. The v1 actor workflow in actor/runtime.rs correctly gates its SleepTsKey deletion inside the allocated-status branch, consistent with this fix.

Both the UDB key deletion and state.sleep_ts = None are correctly gated together on allocation.is_some(), keeping the FDB key and in-memory state in sync.

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Potential Concerns

1. No regression test added

The PR does not add a test for this scenario. A test covering "sleeping actor fails to allocate, sleep_ts remains set" would prevent regressions. Non-blocking given existing test infrastructure, but worth a follow-up.

2. PR description is unfilled

The PR body does not describe what the bug was, what caused it, or how it was found/tested. A short description of the scenario would help with future archeology.

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Code Style

No issues. Logging follows tracing::* structured-field convention, no println!/eprintln! introduced, comment style matches surrounding code, hard tabs used correctly.

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Verdict

Approve. The fix is correct, minimal, and matches the pattern used in the v1 actor workflow.