Bump unit test CI runner to 8x to fix OOM

[lawrencecchen]

Summary

• The TerminalControllerSocketSecurityTests added in Map Shift+Enter to raw newline in Ghostty #2355 cause ghostty surface allocation to OOM on the 6-core WarpBuild runner (error.OutOfMemory), failing 3 socket tests that were previously passing.
• Bumps the tests job runner from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x for more memory headroom.

Test plan

• CI on this PR should show the 3 TerminalControllerSocketSecurityTests passing (or at least no longer OOM-ing)

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Summary by cubic

Bump CI unit test runner from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x to stop OOM failures in TerminalControllerSocketSecurityTests. This adds memory headroom for ghostty surface allocation so the three socket tests no longer fail.

^{Written for commit a2647e6. Summary will update on new commits.}

Summary by CodeRabbit

• Chores
  • Updated CI infrastructure configuration to optimize test job execution environment.

Note: This is an internal infrastructure change with no impact on product features or functionality.

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[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 49baeac3-50aa-453a-a02a-d2a1275692ad

📥 Commits

Reviewing files that changed from the base of the PR and between 112358e and a2647e6.

📒 Files selected for processing (1)

• .github/workflows/ci.yml

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📝 Walkthrough

Walkthrough

The CI workflow's tests job runner is upgraded from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x in the GitHub Actions configuration, providing access to a higher-tier WarpBuild macOS arm64 machine for test execution.

Changes

Cohort / File(s)	Summary
CI Configuration .github/workflows/ci.yml	Updated the tests job's runs-on runner label from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x to use a higher-capacity WarpBuild macOS arm64 machine instance.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related PRs

• Split CI: GitHub runners for tests, Depot for perf regression #773: Previously modified the same tests job runner selection in the CI workflow configuration.
• Migrate CI/CD to WarpBuild, consolidate test jobs #1501: Also changed the tests job's runner label in .github/workflows/ci.yml to a different WarpBuild macOS variant.
• Switch nightly builds to macOS Tahoe runner #2231: Updated GitHub Actions runner selection by modifying WarpBuild macOS runner variants in workflow files.

Poem

🐰 A rabbit hops with glee and cheer,
The runner now more mighty here!
From 6x to 8x, stronger still,
Tests shall race down CI's hill! ⚙️🏃

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely summarizes the main change: bumping the CI runner to an 8x machine to fix OOM failures.
Description check	✅ Passed	The description covers the Summary and Test plan sections well, explaining the problem and the solution. However, Testing, Demo Video, Review Trigger, and Checklist sections are missing or incomplete.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch ci-bigger-runner

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[cubic-dev-ai]

No issues found across 1 file

[greptile-apps]

Greptile Summary

This PR bumps the WarpBuild runner for the tests CI job from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x to resolve error.OutOfMemory failures introduced by TerminalControllerSocketSecurityTests (PR #2355), which allocate Ghostty surfaces and exhaust memory on the 6-core runner.

• The change is surgical — only the tests job is affected; tests-build-and-lag and ui-regressions remain on warp-macos-15-arm64-6x as they don't exhibit the same memory pressure.
• No logic, configuration, or test code changes are involved.
• The workflow-guard-tests job validates that WarpBuild self-hosted runners are used, but those guards check for runner presence rather than a specific label, so no guard script updates are needed.

Confidence Score: 5/5

Safe to merge — single-line runner label bump with no logic changes.

The change is minimal and targeted: one runner label substitution in one CI job. No code, test logic, or configuration beyond the runner size is altered. The other two macOS jobs that don't exhibit OOM are deliberately left on the smaller runner, which is correct. No P1/P0 issues found.

No files require special attention.

Important Files Changed

Filename	Overview
.github/workflows/ci.yml	Single-line runner bump from warp-macos-15-arm64-6x to warp-macos-15-arm64-8x for the tests job only; other jobs (tests-build-and-lag, ui-regressions) remain on 6x as they are not affected by the OOM.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    PR[Pull Request / Push to main] --> WG[workflow-guard-tests\nubuntu-latest]
    PR --> RD[remote-daemon-tests\nubuntu-latest]
    PR --> WT[web-typecheck\nubuntu-latest]
    PR --> T[tests\nwarp-macos-15-arm64-8x BUMPED]
    PR --> TBL[tests-build-and-lag\nwarp-macos-15-arm64-6x]
    PR --> UI[ui-regressions\nwarp-macos-15-arm64-6x]

    T --> UT[Run unit tests\nTerminalControllerSocketSecurityTests\nno longer OOM]
    TBL --> LAG[Lag regression\nnot OOM-affected]
    UI --> UIR[UI regressions\nnot OOM-affected]

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_{Reviews (1): Last reviewed commit: "Bump unit test CI runner to 8x to fix OO..." | Re-trigger Greptile}