[ http://issues.apache.org/jira/browse/DERBY-1876?page=comments#action_12437015 ] Knut Anders Hatlen commented on DERBY-1876: -------------------------------------------
To get an impression of the allocation/gc cost for the statistics, I made all the runtime statistics fields in BasicNoPutResultSetImpl, RowResultSet and UnionResultSet static (these are the ResultSet classes used by the query in derby1867.java). I ran derby1876.java ten times with and ten times without the changes. On average, the test used 15% less time with static fields on Solaris, JVM 1.6. On FreeBSD, JVM 1.5, the time spent was 20% lower with static fields. > Investigate overhead of JDBC layer and compiled activation code for simple > embedded read-only, forward ResultSets > ----------------------------------------------------------------------------------------------------------------- > > Key: DERBY-1876 > URL: http://issues.apache.org/jira/browse/DERBY-1876 > Project: Derby > Issue Type: Improvement > Components: JDBC, Performance > Reporter: Daniel John Debrunner > Priority: Minor > Attachments: derby1862.java, derby1876.java > > > For simple ResultSet usage like: > ResultSet rs = ps.executeQuery(); > while (rs.next()) { > rs.getInt(1); > rs.getInt(2); > rs.getInt(3); > } > rs.close(); > it would be interesting to see how much overhead could be removed with simple > changes, or possibly removed if there was a simple ResultSet implementation > for forward only, read-only ResultSet, and the more complete implementation > for all other ResultSet types such as updateable and/or scrollable. Has > introducing updateable ResultSets, for example, degraded the performance of > read-only ResultSets? Could code be changed so that a typical read-only > Resultset is not affected by the code required for richer ResultSets? -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
