Are you using query prefetching? Robert
On Jan 24, 2012, at 1/2410:11 AM , Wernke zur Borg wrote: > > Dear list, > > I have another question. My application converts a huge MS Access > database to a set of XML files by traversing some really big tables with > Select queries and also querying related tables to collect the > information needed for the output. Performance is horribly bad, so I did > some profiling and found that it spends 75% of its CPU time in > org.apache.cayenne.access.ExternalTransaction.close() and another 21% in > org.apache.cayenne.conn.DriverDataSource.getConnection(). Only 2% are > spent in SelectAction.performAction(). > > So it appears that it opens and closes a new connection for every single > select query. I must be doing something wrong here! Where can I tell it > to re-use connections? Or make one big transaction as it is read-only > anyway? Any other hints? I hope I can reduce the processing time to 4% > of what it is now... > > Thanks, > Wernke > > > > > > This email (including any attachments) may contain confidential and/or > privileged > information or information otherwise protected from disclosure. If you are > not the > intended recipient, please notify the sender immediately, do not copy this > message > or any attachments and do not use it or any purpose or disclose its content > to any > person, but delete this message and any attachments from your system. > RHEA System S.A. (RHEA) disclaims any and all liability if this email > transmission > was virus corrupted, altered or falsified. > > If a Non Disclosure Agreement (NDA) exists between RHEA and the receiving > organization, then all contents shall be considered proprietary and covered > under > the NDA. > >
