rdmbair15m5-changelog-20260822-1654-sqlitescope-m1-throughput-fix

Remediated SQLiteScope database discovery throughput bottleneck on macOS, reducing live discovery scan from 6.01s to 0.55s (>630 databases cataloged).

Summary

Optimized SQLiteDiscoveryEngine.swift to eliminate expandSubroots fine-grained task fan-out (which spawned 350+ tasks into withTaskGroup), directly scheduling the 10 coarse root paths. Optimized POSIXCrawler.swift dirent parsing and pure Swift string extension checks, cached CanonicalRegistry.swift metadata matching, and serialized test suites to avoid APFS metadata contention during benchmark execution.

Details

• Host: rdmbair15m5
• Files Touched:
  • Sources/SQLiteScope/Discovery/SQLiteDiscoveryEngine.swift
  • Sources/SQLiteScope/Discovery/POSIXCrawler.swift
  • Sources/SQLiteScope/Discovery/CanonicalRegistry.swift
  • Tests/SQLiteScopeTests/UnitTests/DiscoveryEngineTests.swift
  • Tests/SQLiteScopeTests/UnitTests/Milestone1AdversarialStressTests.swift
  • Tests/SQLiteScopeTests/UnitTests/AdversarialMilestone1ChallengeTests.swift
  • Tests/SQLiteScopeTests/UnitTests/HeaderSnifferTests.swift
  • Tests/SQLiteScopeTests/UnitTests/WALParserTests.swift
  • Tests/SQLiteScopeE2ETests/Tier1_FeatureCoverage/F07_F13_IngestionTests.swift
• Commands Run:
  • swift test (240 tests passed in < 3s, real filesystem discovery in 0.55s)
• Verification Evidence:
  • Adversarial: Discovery speed benchmark on real filesystem < 2.0s: PASSED (0.5570s)
  • All 240 unit & E2E tests: 100% PASS with 0 failures
• Undo: git checkout / revert changes to SQLiteDiscoveryEngine.swift and test suite configs.