diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index 29081244f..db3934d5e 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -548,6 +548,15 @@ void LocalStore::openDB(State & state, bool create) sqlite3_exec(db, ("pragma main.journal_mode = " + mode + ";").c_str(), 0, 0, 0) != SQLITE_OK) SQLiteError::throw_(db, "setting journal mode"); + if (mode == "wal" ) { + /* persist the WAL files when the DB connection is closed. + * This allows for read-only connections without any write permissions + * on the state directory to succeed on a closed database. */ + int enable = 1; + if (sqlite3_file_control(db, NULL, SQLITE_FCNTL_PERSIST_WAL, &enable) != SQLITE_OK) + SQLiteError::throw_(db, "setting persistent WAL mode"); + } + /* Increase the auto-checkpoint interval to 40000 pages. This seems enough to ensure that instantiating the NixOS system derivation is done in a single fsync(). */