On Thu, Mar 28, 2013 at 8:35 AM, Niall O'Reilly <niall.orei...@ucd.ie> wrote: > > On 28 Mar 2013, at 12:09, Jeff Archer wrote: > >> But my most basic question remains. Why is single transaction faster >> than PRAGMA journal_mode = off? >> >> Seems to me that with no journal there should only be single set of >> writes to the actual db and that journaling would double the number of >> writes because data has to be written to journal file as well. >> >> 2.5 sec with journal >> 5.5 sec without journal <= seems like this sould be the smaller number > > Your base-line for comparison is the case of multiple transactions > with journalling. > > When you turn off journalling, you save something; when you > consolidate the activity into a single transaction, you save > something else. What you're seeing is that the saving achieved > with reference to your base-line measurement by using a single > transaction exceeds that achieved by disabling journalling. > > /Niall >
Agreed. But the question is: Why? Without journaling only half as much writing to disk should occur so why would it take longer? _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
