Fix for SQLite3::BusyException: database is locked during parallel platform sync#40
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…platform sync ## Summary (generated via claude) **Problem** `SyncManager#execute_sync` runs all platforms concurrently (`Concurrent::Promises.future`), and each writes to the same SQLite file via `DiffEngine`. With the default rollback journal, a reader blocks a writer, so under contention a write fails within the 5s timeout and raises `database is locked` - silently skipping that program for the cycle. Example: `ERROR [hackerone] Failed to process program xyz_bbp: SQLite3::BusyException: database is locked` **Fix** Configure SQLite for concurrent access in `Database.connect`: - WAL journal mode so readers no longer block the writer (the actual fix) - Busy timeout raised to 10s so writers wait instead of erroring - `synchronous = NORMAL` (recommended WAL pairing) WAL persists in the DB header, so one call covers all pooled connections; `:timeout` is applied per-connection by Sequel.
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JoshuaMart
approved these changes
Jun 24, 2026
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Summary (generated via claude)
Problem
SyncManager#execute_syncruns all platforms concurrently (Concurrent::Promises.future), and each writes to the same SQLite file viaDiffEngine. With the default rollback journal, a reader blocks a writer, so under contention a write fails within the 5s timeout and raisesdatabase is locked- silently skipping that program for the cycle.Example:
ERROR [hackerone] Failed to process program xyz_bbp: SQLite3::BusyException: database is lockedFix
Configure SQLite for concurrent access in
Database.connect:synchronous = NORMAL(recommended WAL pairing)WAL persists in the DB header, so one call covers all pooled connections;
:timeoutis applied per-connection by Sequel.