Patches item #581134, was opened at 2002-07-14 00:09 You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=376687&aid=581134&group_id=22866
Category: JBossCMP Group: v3.1 Status: Open Resolution: None Priority: 5 Submitted By: Georg Schmid (giorgio42) Assigned to: Nobody/Anonymous (nobody) Summary: CMP Performance Patch: call setFetchSize Initial Comment: CMP Performance Patch: call setFetchSize() on PreparedStatement I added the new element <fetch-size> to the elements <defaults> and <entity> in jbosscmp-jdbc.xml as well as to JDBCEntityMetaData and the JDBCEntityBridge. setFetchSize() is a standard method at least for Statement and PreparedStatement since JDBC2.0. In JDBCAbstractQueryCommand, JDBCLoadEntityCommand and JDBCLoadRelationCommand this value is used in a call to setFetchSize() on the PreparedStatement used to retrieve the rows from the database just after the statement has been created. The value controls the number of rows that are fetched from the database in each roundtrip. It may make sense to set the fetch size in other commands, too, but I don't know enough about the JBossQL related commands to be sure. The effects on performance for a simple finder on a table with 8 attributes on Win2K, Oracle8.1.7 thin driver is: fetch size time in milliseconds to get 6000 entries 1 6100 10 1500 (this is the Oracle thin client drivers default setting) 100 1150 5000 1100 Database and JBoss are running on the same system in this setup. The higher the network latency the greater the benefits on the read performance will be. In another setting where the DB server is on the lan several thousand kilometers away changing the fetch size from 10 to 1000 reduces the time to fetch 1500 rows from 20 to 2 seconds (and 0.5 seconds on the fourth repetition). The patch has been written against 3.1.0alpha. (the metadata related parts are just copied and modified from the listCacheMax implementation). Best regards Georg ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=376687&aid=581134&group_id=22866 ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
