Fix slow health summary endpoint#369
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Wiesenwischer merged 3 commits intomainfrom May 5, 2026
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…and adding composite index
The /api/health/{environmentId} endpoint became progressively slower as the
HealthSnapshots table grew on long-running instances. Root cause: the raw SQL
in GetLatestForEnvironment wrapped EnvironmentId in UPPER(), which prevented
SQLite from using the index and forced a full table scan on every request.
Changes:
- Remove UPPER() / ToUpperInvariant() from GetLatestForEnvironment,
RemoveForDeployment, and GetTransitions; pass Guid parameters via
FromSqlInterpolated so EF Core's standard Guid-to-TEXT conversion is used
on both sides of the comparison.
- Replace the single-column EnvironmentId index with a composite
(EnvironmentId, DeploymentId, CapturedAtUtc) index that covers the
"latest snapshot per deployment in environment" query directly.
- Lower the default snapshot retention from 30 to 7 days. With a 30s
collection interval this still yields ~20k snapshots per deployment,
while the UI history view requests only the latest 50.
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added
bug
The CI run for the previous commit failed because: - The migration used MigrationBuilder.DropIndex/CreateIndex, which emit plain DROP/CREATE INDEX without IF [NOT] EXISTS guards. On a baseline-skipped legacy database where the InitialCreate index was never materialised, this throws. - The legacy-DB test fixture only created StackSources, so it was not a realistic stand-in for an EnsureCreated()-era database (which would contain the full baseline schema). Changes: - Switch the index swap to raw SQL with DROP INDEX IF EXISTS / CREATE INDEX IF NOT EXISTS, so the migration is safe regardless of whether the legacy baseline materialised the old single-column index. - Extend CreateLegacyStackSourcesTable to also create a minimal HealthSnapshots table with the InitialCreate-era indexes, so MigrationBaselineTests exercise a realistic legacy schema.
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Summary
The
/api/health/{environmentId}endpoint became progressively slower as theHealthSnapshotstable grew on long-running instances (observed ontest-ux-dokker: skeleton loaders never resolved).Root cause: the raw SQL in
GetLatestForEnvironmentwrappedEnvironmentIdinUPPER(), which prevents SQLite from using the index and forces a full table scan on every request. Compounded by the absence of a composite index covering the(env, deployment, latest)access pattern, and a 30-day default retention that lets the table grow large.Changes
UPPER()/ToUpperInvariant()fromGetLatestForEnvironment,RemoveForDeployment, andGetTransitions. Guid parameters are passed viaFromSqlInterpolatedso EF Core's standard Guid-to-TEXT conversion is used on both sides of the comparison.EnvironmentIdindex with a composite(EnvironmentId, DeploymentId, CapturedAtUtc)index that directly covers the "latest snapshot per deployment in environment" query.AddHealthSnapshotsCompositeIndexperforms the index swap.Test plan
dotnet buildclean (0 errors, 0 new warnings)test-ux-dokkerthat/healthpage loads quickly after deploy