this last bench was Inserting 500000 t1 records and 3000000 t2 records
> MySQLDB... > ~7573 i/s 0:06:36.124 (396124 ms) > Close 0:00:00.001 (1 ms) > HSQLDB... > ~4853 i/s 0:10:18.080 (618080 ms) > Close 0:00:00.005 (5 ms) > H2DB... > ~1874 i/s 0:26:40.641 (1600641 ms) > Close 0:00:08.438 (8438 ms) > > > Le lundi 12 août 2013 12:52:18 UTC+2, Noel Grandin a écrit : >> >> >> On 2013-08-12 06:12, Pierre wrote: >> >> Thanks Thomas but the profiler doesn't showed something interesting. >> Anyway, the issue is related to H2, it doesn't supports massive inserts. >> When the table size > 3 millions rows, it begins to be very slow. Adding >> LOG=0;UNDO_LOG=0;NOLOCK/WHATEVER optmisation just delay the ineluctable >> slow insertions, it optimize a lot but only if < 3 millions rows. >> >> I know that because I created a bench and just looks at the numbers : >> >> >> Two things are at work here: >> >> (1) MySQL and HSQLDB cheat a little by not performing fsync() as often as >> they should, so they are trading off increased risk of losing data against >> better speed >> >> (2) When you create an FK constraint, we create an index on the column to >> speed up the foreign key checking, which it looks like MySQL and HSQLDB do >> not do. This costs us in the insert benchmark because we have to update an >> extra on-disk datastructure. >> >> When I take those two factors out, the numbers start looking roughly >> comparable. >> >> One thing you might want to do when trying to run large volumes of data >> through H2 is to bump up our cache size using something like: >> ";CACHE_SIZE=65536" in the URL. >> >> Our default cache setting is a little conservative for larger deployments. >> >> >> >> -- You received this message because you are subscribed to the Google Groups "H2 Database" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/h2-database. For more options, visit https://groups.google.com/groups/opt_out.
