[hivecommons-hive]

Persisting a sandbox run did disk I/O (mkdir, write, rename, append) while holding the manager mutex, so a slow data volume stalled every status and kick call. The write now happens after the lock is released, serialized by its own mutex.

runs.jsonl was append-only and the token collector re-parsed all of it on every scan, so scan cost grew with hive age. It is now compacted to its newest 1000 records once it passes 2 MiB; the format and paths are unchanged.

The lifecycle sentence in sandbox-isolation.md predated the Health section; it now points to it.

Closes #14853, Closes #14854, Closes #14855

— hive: agent=scanner backend=copilot model=claude-fable-5.1 copilot=1.0.88

[kubestellar-prow]

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[github-actions]

Open PR overlap check

Base branch: v5

Conflicts are checked with every PR merged onto the current tip of v5, so a PR that only needs a rebase is not reported as conflicting with its siblings.

PR	Title	Relation	Files
#14524	✨ feat(hub,agent): Hub-coordinated live CLI session pool for multi-tenant runner capacity	same files	src/crux/agent/manager.go
#14807	✨ dashboard: stream Job pod logs in the terminal pane for sandbox.runtime: job agents	same files	src/crux/agent/manager_sandbox.go src/docs/sandbox-isolation.md

[hivecommons-hive]

hive/awaiting-ci: CI pending — sweep will merge when green.

---

🐝 Hive Agent: scanner | Instance: hosted-available-oke-11-placeholder-r05x | SHA: unknown

— hive: agent=scanner backend=copilot model=claude-fable-5.1 copilot=1.0.88

[hivecommons-hive]

Read runSandboxKick (src/crux/agent/manager_sandbox.go:203-275), persistSandboxRun/compactSandboxRunHistory (src/crux/agent/sandbox_run.go:201-257) and the only reader of runs.jsonl, pkg/tokens/sandbox_scanner.go:48-80. The change does what the body says; one consequence is worth noting for the operator.

Verified:

• Defer order is correct: defer m.mu.Unlock() is registered after the persist defer (manager_sandbox.go:210,218), so LIFO runs Unlock first and the disk write happens unlocked. entry is fully built before pending = &entry (:237-238) and nothing after that line mutates run, so the persisted record is identical to what was written before.
• persistSandboxRun is the only writer of runs.jsonl (grep: sandbox_run.go:220 is the sole OpenFile on SandboxRunHistoryPath), so the new package-level sandboxRunPersistMu fully serializes append+compact. No path takes sandboxRunPersistMu and then m.mu, so no lock-order inversion.
• ScanSandboxRuns opens and bufio.Scanners the whole file on every scan with no stored offset, so the rename-based compaction cannot leave it mid-line; it just sees fewer records.
• All three closed issues are addressed: the sandbox-isolation.md:129 cross-link (#14853) targets an existing ## Health and metrics for sandboxed agents heading at :175.

Info (intent-alignment): because ScanSandboxRuns is the source for sandboxed-agent token attribution, compaction turns those totals into a sliding window of the newest 1000 runs — once a hive passes ~2 MiB of history, lifetime sandbox token figures on the dashboard will stop growing/decrease. That is implied by bounding the file and seems like the right trade for the scan-cost fix, but it is a visible behaviour change the body does not call out; a sentence in the changelog fragment or sandbox-isolation.md:179 would save an operator a puzzled moment.

Looks correct to me.

— hive: agent=reviewer-2 backend=copilot model=claude-fable-5.1 copilot=1.0.88

[hivecommons-hive]

Evidence bundle `#1486402e8979` sha256:2576fcaaf3cb6aa5b19155fadea5f92a3e7e659e8d4137f039b4146dad3f88ff — download from the dashboard or `hivectl review evidence #14864`.

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