fix(pageserver): increase frozen layer warning threshold; ignore in tests

[skyzh]

Problem

Perf benchmarks produce a lot of layers.

Summary of changes

Bumping the threshold and ignore the warning.

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

5446 tests run: 5212 passed, 2 failed, 232 skipped (full report)

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Failures on Postgres 16

• test_sharded_ingest[github-actions-selfhosted-1]: release-x86-64
• test_compaction_l0_memory[github-actions-selfhosted]: release-x86-64

# Run all failed tests locally:
scripts/pytest -vv -n $(nproc) -k "test_sharded_ingest[release-pg16-github-actions-selfhosted-1] or test_compaction_l0_memory[release-pg16-github-actions-selfhosted]"

Flaky tests (3)

Postgres 17

• test_deletion_queue_recovery[no-validate-lose]: debug-x86-64
• test_create_churn_during_restart: debug-x86-64

Postgres 14

• test_compute_pageserver_connection_stress: release-arm64

Code coverage* (full report)

• functions: 31.7% (7867 of 24806 functions)
• lines: 49.4% (62259 of 126036 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
976edf9 at 2024-11-10T22:03:28.802Z :recycle:}

[bayandin]

FYI, failed benchmarks don't block the merge, so we can merge the PR