It's not that commits are better tuned than rollbacks. For every
database (Informix, DB2, Oracle,...) changes are done immediately, so a
commit simply marks the transaction as ended and frees locks/advances
SCN. A rollback must put everything back again as it was before,
undoing the modifications, so it's evident that a rollback will always
be slower than a commit and there is no solution to that. Obviously,
should a crash occur before a commit, pending transaction is rolled
back at instance startup, because it's not marked as committed. That's
the function of redo logs.
Basically, substituting commits for rollbacks, you have made tests
twice faster, eliminating the rollback part.
Received on Thu Sep 15 2005 - 10:26:34 CDT
