In my tests, with all these settings, if you hammer SQLite with reads/writes, it won't be able do any WAL checkpoints (needs no active transactions), and the WA

In my tests, with all these settings, if you hammer SQLite with reads/writes, it won't be able do any WAL checkpoints (needs no active transactions), and the WAL file can quickly grow from, say, 8 MB to tens, hundreds of GB until your machine runs of out space (the docs mention this). So my default is to also keep track of the size of the WAL file, and if it grows beyond some threshold, temporarily suspend all reads/writes and checkpoint manually.