Performance of Session Stateless Bean in WebSphere with connection to DB

Question

Im using WebSphere Advanced Single Server Edition Version 4.0.1. and a WebSphere DataSource to get my connections to Microsoft SQL 2000 (using netdirect's JSQLDriver).
For the EJB I set the transaction to 'requieresNew'.
For testing purposes I had been testing some code I'll be using in a Session Stateless Bean inside a servlet's method. In my servlet I use one single connection and preparedStatements to improve performance.
When I test it on the Servlet, this process takes around 3 minutes to complete, but when I put this code inside a Session Stateless Bean and call it from this servlet's method, it takes around 30 minutes to complete!. How is this possible?!
Worst of all, when the EJB ends and the process returns to the Servlet, it throws me this exception.
com.ibm.websphere.ce.cm.StaleConnectionException: class com.ibm.ejs.cm.proxy.PreparedStatementProxy is closed.
The code uses some utilities from a Framework we created, but I really doubt it affects the performance since I put such classes in a jar file and the EJB is accessing such classes correctly.
I thought that maybe I was missing something related with how I get the connection inside the EJB, but I had no luck trying to figure this out.
This is the code in my EJB, commented code was in use when this code was tested in the method of the servlet (some code has been removed or modified, so I just left the 'main' body of the code):
package cmx.ejb;
import cmx.common.*;
import java.util.*;
import qsi.sys.db.*;
import qsi.sys.util.*;
import java.rmi.*;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.*;
import javax.ejb.*;
import javax.naming.*;
import javax.rmi.*;
import javax.sql.DataSource;
* Bean implementation class for Enterprise Bean: SimuladorEJB
public class SimuladorEJBBean implements javax.ejb.SessionBean {
     private javax.ejb.SessionContext mySessionCtx;
private Context ctx;
private DataSource ds;
private static final int TCONSUMO = 4;
private static final int CARACEQ = 6;
private static final int PPRODUC = 9;
private static final int PPUNTA = 12;
private static final int UTONHR = 8;
private static final int TPRODUCC = 3;
private Vector val = null;
private Vector vecArea = null;
private String query;
private Object[] params;
private int numAreas;
private int vSecDetHE;
//All the prepared statements I'll use in my process
private PreparedStatement pstmSelectSerial = null;
private PreparedStatement pstmUpdateSerial = null;
private PreparedStatement pstmgetPPEquipos = null;
private PreparedStatement pstmgetTransfers = null;
private PreparedStatement pstmaddRProduccion = null;
private PreparedStatement pstmupdInventario = null;
private PreparedStatement pstmgetServicios = null;
private PreparedStatement pstmaddConsumo = null;
private PreparedStatement pstmgetAreaEquipos = null;
private PreparedStatement pstmfindCE = null;
private PreparedStatement pstmcontEventoLogEq = null;
private PreparedStatement pstmaddLog = null;
private PreparedStatement pstmfindCaract = null;
private PreparedStatement pstmfindComposicion = null;
private PreparedStatement pstmfindCombAlt = null;
private PreparedStatement pstmaddInventarioH = null;
private PreparedStatement pstmgetAlmMatREM = null;
private PreparedStatement pstmfindAlmacen = null;
private PreparedStatement pstmcontEventoLogAlm = null;
private PreparedStatement pstmgetAlmacenes = null;
private PreparedStatement pstmfindInvHora = null;
private PreparedStatement pstmgetPeriodoHorario = null;
private PreparedStatement pstmgetProgramaCE = null;
private PreparedStatement pstmgetProgramaPP = null;
private PreparedStatement pstmgetProgramaParo = null;
private PreparedStatement pstmgetPrograma = null;
     * getSessionContext
     public javax.ejb.SessionContext getSessionContext() {
          return mySessionCtx;
     * setSessionContext
     public void setSessionContext(javax.ejb.SessionContext ctx) {
          mySessionCtx = ctx;
     * ejbActivate
     public void ejbActivate() {
     * ejbCreate
     public void ejbCreate() throws javax.ejb.CreateException {
System.out.println("ejbCreate()");
try {
Hashtable parms = new Hashtable();
parms.put(Context.INITIAL_CONTEXT_FACTORY, "com.ibm.websphere.naming.WsnInitialContextFactory");
ctx = new InitialContext(parms);
ds = (DataSource)ctx.lookup("jdbc/datasource");
}catch (Exception e){
e.printStackTrace();
     * ejbPassivate
     public void ejbPassivate() {
     * ejbRemove
     public void ejbRemove() {
System.out.println("ejbRemove()");
     pstmSelectSerial = null;
     pstmUpdateSerial = null;
     pstmgetPPEquipos = null;
     pstmgetTransfers = null;
     pstmaddRProduccion = null;
     pstmupdInventario = null;
     pstmgetServicios = null;
     pstmaddConsumo = null;
     pstmgetAreaEquipos = null;
     pstmfindCE = null;
     pstmcontEventoLogEq = null;
     pstmaddLog = null;
     pstmfindCaract = null;
     pstmfindComposicion = null;
     pstmfindCombAlt = null;
     pstmaddInventarioH = null;
     pstmgetAlmMatREM = null;
     pstmfindAlmacen = null;
     pstmcontEventoLogAlm = null;
     pstmgetAlmacenes = null;
     pstmfindInvHora = null;
     pstmgetPeriodoHorario = null;
     pstmgetProgramaCE = null;
     pstmgetProgramaPP = null;
     pstmgetProgramaParo = null;
     pstmgetPrograma = null;
public void GenerarSimulacion(int pidSimulacion, String pfini, String pffin, int cveEntidad, int cveUsuario) throws Exception{
System.out.println("GenerarSimulacion()");
System.out.println("***Simulacion " + pidSimulacion + " en proceso...***");
Calendar inicioProceso = Calendar.getInstance();//Tiempo en que empezo el Proceso
Calendar finProceso = null;//Tiempo en que termino el Proceso
     Connection cnn = null;
//boolean autoCommit = false;
     try{
     cnn = ds.getConnection();
autoCommit = cnn.getAutoCommit();
cnn.setAutoCommit(false);
     cnn.setTransactionIsolation(Connection.TRANSACTION_READ_UNCOMMITTED);
pstmSelectSerial = cnn.prepareStatement("select iValor from CatConsecutivo where vcConsecutivo=?");
pstmUpdateSerial = cnn.prepareStatement("update CatConsecutivo set iValor = iValor+1 where vcConsecutivo=?");
pstmgetPPEquipos = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getPPEquipos"));
pstmgetTransfers = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getTransfers"));
pstmaddRProduccion = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.addRProduccion"));
pstmupdInventario = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.updInventario"));
pstmgetServicios = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getServicios"));
pstmaddConsumo = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.addRConsumo"));
pstmgetAreaEquipos = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getAreaEquipos"));
pstmfindCE = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findCE"));
pstmcontEventoLogEq = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.contEventoLogEq"));
pstmaddLog = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.addLog"));
pstmfindCaract = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findCaract"));
pstmfindComposicion = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findComposicion"));
pstmfindCombAlt = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findCombAlt"));
pstmaddInventarioH = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.addInventarioH"));
pstmgetAlmMatREM = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getAlmMatREM"));
pstmfindAlmacen = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findAlmacen"));
pstmcontEventoLogAlm = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.contEventoLogAlm"));
pstmgetAlmacenes = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getAlmacenes"));
pstmfindInvHora = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.findInvHora"));
pstmgetPeriodoHorario = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getPeriodoHorario"));
pstmgetProgramaCE = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getProgramaCE"));
pstmgetProgramaPP = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getProgramaPP"));
pstmgetProgramaParo = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getProgramaParo"));
pstmgetPrograma = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getPrograma"));
pstmgetAreaEquipos = cnn.prepareStatement(Manager.getParameter("cmx.admin.inicioSesion.getAreaEquipos"));
Map hmEqMat = null;
Iterator itEqMat = null;
Map.Entry meEqMat = null;
Map hmInvAlm = null;
Iterator itInvAlm = null;
Map.Entry meInvAlm = null;
Map hmPunta = null;
Iterator itPunta = null;
Map.Entry mePunta = null;
Iterator itPuntaEq = null;
HashMap hmPuntaEq = null;
Vector vecPuntaEq = null;
Iterator itPPEq = null;
HashMap hmPPEq = null;
Vector vecPPEq = null;
Iterator itCar = null;
HashMap hmCar = null;
Vector vecCar = null;
Iterator itLog = null;
HashMap hmLog = null;
Vector vecLog = null;
Iterator itCA = null;
HashMap hmCA = null;
Vector vecCA = null;
Iterator itCom = null;
HashMap hmCom = null;
Vector vecCom = null;
Iterator it = null;
HashMap hm = null;
Vector vecEv = null;
Iterator itEq = null;
HashMap hmEq = null;
Vector vecEq = null;
Vector vecSim = null;
Date d;
String sDSim = "";
Date dDiaPrevio;
String sDiaPrevio = "";
String consulta;
int vContador= 0;
int hr=0;
long vDiaPrevio = 0;
Integer idInvH;
Integer idProd;
Integer idCons;
Integer idLog;
int vCont = 0;
int vCiclo = 0;
int vArea = 0;
int vAreaAct = 0;
int vPuntaEquipo = 0;
// Periodo de Simulacion
long fini = getCurrDate(pfini);
long ffin = getCurrDate(pffin);
// Variables Generales
int vSecuencial = 0;
int vEvento = 0;
float vCostoE = 0;
int vAlmacenREM = 0;
// Variables de Transferencia
float vCantidad = 0;
int vTipoMov = 0;
int vUMedida = 0;
int vAlmacenTr = 0;
float vNIni = 0;
float vNMin = 0;
float vNMax = 0;
float vNAct = 0;
// Variables de Equipos
int vPPMaterial = 0;
int vPPEquipo = 0;
int vPPArea = 0;
int vMaterial = 0;
int vCaractEq = 0;
int vParo = 0;
int vEstatusParo = 0;
int vEstatus = 0;
float vMinPunta = 0;
float vPorcPunta = 0;
float vProporcion = 0;
float vTPH = 0;
float vGasto = 0;
float vKwNoProd = 0;
float vKwProd = 0;
int vAlmacen = 0;
// Variables de Composicion de Materiales
int vMaterialCom = 0;
float vPorcCom = 0;
float vFactorCC = 0;
int vTipoMovCom = 0;
int vUMedidaCom = 0;
int vAlmacenCom = 0;
float vNIniCom = 0;
float vNMinCom = 0;
float vNMaxCom = 0;
float vNActCom = 0;
int vMaterialCA = 0;
int vUMedidaCA = 0;
int vAlmacenCA = 0;
float vNIniCA = 0;
float vNMinCA = 0;
float vNMaxCA = 0;
float vNActCA = 0;
int vOk=0;
int h=0;
boolean vbOk=false;
boolean swArea=true;
Calendar dtH1;
vecSim = new Vector();
vecSim.add(new Integer(pidSimulacion));
for (long ld=fini; ld<=ffin; ld=getNextDate(new Date(ld), 1))
{   d = new Date(ld);
//The process which calls find(), upd(), AplicaEvento() and GetCostoEnergia() methods several times.
//The methods find() and upd() uses a util class (DataDB) which basically assigns the params to the PreparedStatement and executes it, returning the results in a Vector.
} // for ld : Dia de Simulacion
//Cerrar la transaccion
}catch (Exception e){
          System.out.println("rollback...");
               mySessionCtx.setRollbackOnly();
     System.out.println("rollback ok!");
System.out.println(e.toString());
               throw e;
}finally{
finProceso = Calendar.getInstance();
finProceso.setTime(new java.util.Date(finProceso.getTime().getTime() - inicioProceso.getTime().getTime()));
System.out.println("***Simulacion " + pidSimulacion + " procesada en: " + finProceso.get(Calendar.MINUTE) + ":" + finProceso.get(Calendar.SECOND) + "." + finProceso.get(Calendar.MILLISECOND) + ".***");
try {
if (cnn!=null && !cnn.isClosed()) {
          System.out.println("close ok?");
cnn.close();
               System.out.println("close ok!");
}catch (SQLException sqle){
sqle.printStackTrace();
System.out.println("commit ok?");
cnn.commit();
System.out.println("commit ok!");
}catch (Exception e){
e.printStackTrace();
System.out.println(e.toString());
try {
if (cnn!=null && !cnn.isClosed()) {
               System.out.println("rollback ok?");
                         cnn.rollback();
          System.out.println("rollback ok!");
}catch (SQLException sqle){
sqle.printStackTrace();
}finally{
finProceso = Calendar.getInstance();
finProceso.setTime(new java.util.Date(finProceso.getTime().getTime() - inicioProceso.getTime().getTime()));
System.out.println("Simulacion procesada en: " + finProceso.get(Calendar.MINUTE) + ":" + finProceso.get(Calendar.SECOND) + "." + finProceso.get(Calendar.MILLISECOND) + ".***");
try {
if (cnn!=null && !cnn.isClosed()) {
               System.out.println("autocommit ok?");
               cnn.setAutoCommit(autoCommit);
          System.out.println("autocommit ok!");
          System.out.println("close ok?");
cnn.close();
               System.out.println("close ok!");
}catch (SQLException sqle){
sqle.printStackTrace();
private float GetCostoEnergia(float pfKw, long plFecha, int piHora,int cveEntidad) throws Exception {
float exito = -1;
//calculations and has access to DB throught method find()
return exito;
private int AplicaEvento(int pidMaterial, int pidEvento, int pidSecuencial, int pidSimulacion, long plFecha, int piHora) throws Exception {
int exito = -1;
//calculations and has access to DB throught method find()
return exito;
private Iterator find(PreparedStatement pstm, Vector values) throws Exception {
params = (values!=null)? values.toArray() : null;
Vector data = DataDB.executeQuery(pstm, params); //This util class is in a external jar file, such util basically assigns the params to the PreparedStatement and executes it, returning the results in a Vector.
return data.iterator();
private int upd(PreparedStatement pstm, Vector values) throws Exception {
params = values.toArray();
return DataDB.executeUpdate(pstm, params); //This util class is in a external jar file, such util basically assigns the params to the PreparedStatement and executes it.
Help will be REALLY appreciated!
Thanks in advance.

Answer 1

Thanks Paul for your comments.
In fact, I call my EJB in the servlet just once. Im sure calling the same EJB. My project requieres it to be stateless.
This is my last log
1/2/03 13:15:00:481 CST] 17fac55b SystemOut U -ejbCreate()-
[1/2/03 13:15:00:591 CST] 17fac55b SystemOut U jdbc/xa/oye
[1/2/03 13:15:00:651 CST] 17fac55b SystemOut U -GenerarSimulacion()-
[1/2/03 13:15:00:741 CST] 17fac55b SystemOut U ***Simulacion 32 en proceso...??***
[1/2/03 13:15:01:012 CST] 17fac55b SystemOut U JSQLConnect(2.2721) Trial license - expires on:Tue Jan 07 13:01:32 CST 2003, unlimited connections
[1/2/03 13:15:01:092 CST] 17fac55b SystemOut U Connection OK!
[1/2/03 13:15:01:392 CST] 17fac55b SystemOut U PreparedStatements OK!
[1/2/03 13:15:01:402 CST] 17fac55b SystemOut U Comenzando Sim...
I forgot to mention that I create a connection (autocommit false) at the begining of my servlet, which I use throught all the servlet, then I call the EJB, and after the EJB succeds I also close the transaction in the Servlet (to commit what is on the servlet, not the EJB). Thats why I set the transaction in the EJB to requiresNew, so after the EJB ends it commits its own transaction, Am I right?.
The Exception I get I think its because the connection used in the servlet timed out while waiting for the EJB to finish.
This issue has become urgent, so please if you know why I have this problem reply ASAP.
Thanks!