[magma-beef]

Summary

Bug fix to the pre-unmount trim from #147 (v1 line; #148 is the same fix on release/v2). trimFilesystem ran timeout <secs> sudo fstrim ...: the unprivileged timeout cannot signal the root-owned sudo/fstrim it spawned (EPERM), so the host budget never bounded the trim and a slow fstrim could outlive it and keep the buildkit mount busy at unmount.

- timeout ${timeoutSecs} sudo fstrim -v${minimum} -- "${mountPath}"
+ sudo timeout ${timeoutSecs} fstrim -v${minimum} -- "${mountPath}"

sudo passes timeout's exit 124 through, so the timeout classification in setup_builder.ts is unchanged. Verified on a runner image: timeout 2 sudo sleep 30 leaves sudo sleep 30 running; sudo timeout 1 sleep 30 exits 124 with the child gone.

Start here: src/main.ts (trimFilesystem). dist/ is the regenerated bundle.

No behavior change in prod today: hosts send budget 0, so the trim is skipped before this command runs.

Checks: lefthook pre-commit (prettier, eslint, tsc, build, dist diff).

Link to Devin session: https://app.devin.ai/sessions/2e17815c306b4c3cb7af4f6bce008a66
Open in Devin Desktop: https://app.devin.ai/desktop/session/2e17815c306b4c3cb7af4f6bce008a66?variant=devin
Requested by: @magma-beef

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^{Open in [code]smith · Need help on this PR? Tag @codesmith-bot with what you need.}

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🟢 Devin Review found nothing to fix · View findings

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^{Open in [code]smith · Need help on this PR? Tag @codesmith-bot with what you need. (Staging)}

[devin-ai-integration]

I'll fix CI failures and address comments from users with write access. I'll skip comments containing "(aside)".

• Disable automatic comment, CI, and merge conflict monitoring

[blacksmith-staging]

Slow fstrim stops at the budget

After, the trim returns as a timeout at the 3s budget with nothing left running for both stand-ins. Before, a single-process fstrim was already stopped at 3s here; only when the work ran in a child process did it outlive the budget and hold the trim for 20s.

_Merge-base

_{This PR b65d93d8}

Also checked · 1 match

Real fstrim outcomes unchanged

_{Proof on b65d93d8 · mocked: fstrim (a genuinely slow trim needs a large RBD-backed sticky disk; a root-owned stub th...) · not run: Blacksmith host agent / sticky disk API (not needed) · Did Proof get it right? Yes · No}

View full Proof report

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.