cayenne-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Robert Zeigler <robert.zeig...@roxanemy.com>
Subject Re: Performance question
Date Tue, 24 Jan 2012 20:39:50 GMT
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.
> 
> 


Mime
View raw message