Oracle DB - Application Continuity - How to test it? - oracle

Question

How to Test/POC application continuity concept. I tried making the code to hold connections so that the application is not able get the connections and it tries to get from the pool. I am sure this is not the right way of testing application continuity, but I don't know how to create a proper scenario.
Is it the only way to bring down db while a transaction is in progress ?
I used the below code to simulate AC where a procedure is called 20 times in 20 threads with a new connection everytime. I am creating a scenario where one thread goes and waits for a connection, times-out as not getting connection in time, and then retires to get a connection, IS This a proper AC test. (Below is test class)
package com.ac;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.Statement;
import oracle.ucp.jdbc.PoolDataSourceFactory;
import oracle.ucp.jdbc.PoolDataSource;
import oracle.ucp.jdbc.ValidConnection;
import java.sql.ResultSet;
public class App {
public static void main(String[] args) {
try {
new App().acSimulation();
} catch (Exception e) {
e.printStackTrace();
}
}
public void acSimulation() throws Exception{
final PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();
pds.setConnectionFactoryClassName("oracle.jdbc.replay.OracleDataSourceImpl");
System.out.println("connection factory set");
String URL = "jdbc:oracle:thin:#(DESCRIPTION = (TRANSPORT_CONNECT_TIMEOUT=3) (RETRY_COUNT=20)(FAILOVER=ON) " +
" (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)) (CONNECT_DATA = " +
" (SERVER = DEDICATED) (SERVICE_NAME=orcl)))";
System.out.println("Using URL\n" + URL);
pds.setURL(URL);
pds.setUser("system");
pds.setPassword("oracle");
pds.setInitialPoolSize(1);
pds.setMinPoolSize(1);
pds.setMaxPoolSize(3);
pds.setConnectionWaitTimeout(10);
// RAC Features
pds.setConnectionPoolName("Application Continuity Pool");
pds.setFastConnectionFailoverEnabled(true);
// use srvctl config nodeapps to get the ONS ports on the cluster
// pds.setONSConfiguration("nodes=192.168.100.30:6200,192.168.100.32:6200");
System.out.println("pool configured, trying to get a connection");
// final Connection conn = null;
final Connection conn = pds.getConnection();
if (conn == null || !((ValidConnection) conn).isValid()) {
System.out.println("connection is not valid");
throw new Exception ("invalid connection obtained from the pool");
}
if ( conn instanceof oracle.jdbc.replay.ReplayableConnection ) {
System.out.println("got a replay data source");
} else {
System.out.println("this is not a replay data source. Why not?");
}
System.out.println("got a connection! Getting some stats if possible");
oracle.ucp.jdbc.JDBCConnectionPoolStatistics stats = pds.getStatistics();
System.out.println("\tgetAvailableConnectionsCount() " + stats.getAvailableConnectionsCount());
System.out.println("\tgetBorrowedConnectionsCount() " + stats.getBorrowedConnectionsCount() );
System.out.println("\tgetRemainingPoolCapacityCount() " + stats.getRemainingPoolCapacityCount());
System.out.println("\tgetTotalConnectionsCount() " + stats.getTotalConnectionsCount());
System.out.println(((oracle.ucp.jdbc.oracle.OracleJDBCConnectionPoolStatistics)pds.getStatistics()).getFCFProcessingInfo());
System.out.println("Now working");
int i=0;
while(i < 20){
new Runnable() {
public void run() {
try {
seperateInstance(conn, pds);
} catch (SQLException e) {
e.printStackTrace();
}
}
}.run();
i++;
}
}
private void seperateInstance(Connection conn, PoolDataSource pds) throws SQLException{
java.sql.CallableStatement cstmt = null;
oracle.ucp.jdbc.JDBCConnectionPoolStatistics stats = pds.getStatistics();
conn = pds.getConnection();
cstmt = conn.prepareCall("{call P_M_emp(?,?)}");
cstmt.setLong(1, 1);
cstmt.setString(2, "TEST");
cstmt.execute();
System.out.println("Statement executed. Now closing down");
System.out.println("Almost done! Getting some more stats if possible");
stats = pds.getStatistics();
System.out.println("\tgetAvailableConnectionsCount() " + stats.getAvailableConnectionsCount());
System.out.println("\tgetBorrowedConnectionsCount() " + stats.getBorrowedConnectionsCount() );
System.out.println("\tgetRemainingPoolCapacityCount() " + stats.getRemainingPoolCapacityCount());
System.out.println("\tgetTotalConnectionsCount() " + stats.getTotalConnectionsCount());
System.out.println(((oracle.ucp.jdbc.oracle.OracleJDBCConnectionPoolStatistics)pds.getStatistics()).getFCFProcessingInfo());
try {
Thread.currentThread().sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("Closing connection "+ conn);
cstmt.close();
conn.close();
conn = null;
}
}
I got the code from below site and modified a bit to add threads and simulate AC. But I am unable to get a replayable datasource.
https://martincarstenbach.wordpress.com/2013/12/13/playing-with-application-continuity-in-rac-12c/

Answer 1

To test Application Continuity you can kill the sessions on the server by doing ALTER SYSTEM KILL SESSION 'sid,serial#' which will simulate a failure.