It's needed specifically when setting WAL, because on module loading, each child creates its own DB connection and sets the WAL (or other options you might set), and it all happens roughly at the same time. Without setting the busy-timeout, starting of kamailio will fail due to locking issues with sqlite.

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#### Description <!-- Describe your changes in detail --> You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/4028

-- Commit Summary --

* db_sqlite: Add busy timeout param to improve concurrency.

-- File Changes --

M src/modules/db_sqlite/db_sqlite.c (52) M src/modules/db_sqlite/db_sqlite.h (1) M src/modules/db_sqlite/dbase.c (13) M src/modules/db_sqlite/doc/db_sqlite_admin.xml (48)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/4028.patch https://github.com/kamailio/kamailio/pull/4028.diff