To be able to rollback transactions, sqlite write a journal file on disk which is kind of slow. When one doesn't care about dataloss (ex a dev wiki), it would be nice to have the journal held in memory and thus saving disk I/O.

Doc:
http://www.sqlite.org/pragma.html#pragma_journal_mode

Whenever a connection to a sqlite file is made, one can issue the command:

pragma journal_mode=memory;

Should probably be yet another global variable such as $wgSqliteJournalMode

Version: 1.23.0
Severity: enhancement