I'm working on a database application that is shut down quite often. At each shutdown, only a small amount of data is written to the DB, which is in WAL mode. Due to HW restrictions, I had to reduce the total amount of data written to disk, which is why I have activated SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE.
This works fine as long as TRUNCATE checkpoints are issued from within my code. However, since the amount of data that is written into the DB at each shutdown varies, it is suboptimal to just trigger the checkpoint at each n-th shutdown. To get a better trade-off between the amount of written data and WAL size, it would be nice to trigger the checkpoints based on the size of the WAL. It seems that PRAGMA journal_size_limit doesn't help here: the WAL file grows infinitely when no checkpoints are issued from within my code. Is this the expected behavior (I guess so) or a configuration problem? Note that PRAGMA wal_autocheckpoint also doesn't help, but this is pretty obvious because it only triggers a PASSIVE checkpoint. I would rather not access the WAL file directly (bypassing SQLite) for checking it's size. Does anybody have a proper solution for this problem? P.S.: As a test, I have modified sqlite3WalClose() (and the place where it is called) to delete/truncate the WAL when journal_size_limit is reached. I had to change only two lines, but of course I am not sure that my change doesn't break anything. -- Stefan Kniep _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
