Oracle JDBC poor performance at high volume

Question

We have a requirement to read through huge ASCII files (120 million records, 9 gigs uncompressed) and do database lookups on 4 values in each record. I have written a multithreaded application to read through one of the files and perform the lookups.
Each Thread has a dedicated Connection object from which I create a CallableStatement object that I reuse throughout the lifecycle of the Thread. I use a CallableStatement object to call a stored procedure with INOUT parameters that effectively wraps the 4 lookups into one database roundtrip.
The issue is that we can't seem to top 240 lookups per second, which is just not fast enough for our needs. Our DBA says that while we are not taxing the Oracle database in the least, we are eating up a TON of processor utilization (20 Connections ups the load on a Solaris 8 4-way box from anywhere from 10 to 20). So if we up the number of threads, any performance gain we would hope to get is nullified by the slowdown brought on by the increased load.
I'll be happy to post sample code if anyone shows further interest. And yes, we've considered doing a sql*loader direct load of the file, and then doing the validation on the DB via PL/SQL. I'm just trying to find out if this is a limitation of the Oracle JDBC drivers (we've had similar results with thin and OCI), or if I'm doing something terribly wrong.

Answer 1

For the purposes of readability (and client confidentiality) I removed about 400 lines of processing logic that from performance testing I found to not be the bottleneck.. it's all in the cs.executeUpdate(). It should compile.
import java.sql.*;
import java.io.*;
import java.util.*;
public class Sample extends Thread{
     private static final String url = "jdbc:oracle:oci8:@instance";
     private static final String dbUser = "user";
     private static final String dbPass = "pass";
     private static BufferedReader br;
     // instance members for each thread
     private Connection con;
     private     CallableStatement cs = null;
     public static void main(String args[]){
          try{
               int numThreads = Integer.parseInt(args[1]);
               br = new BufferedReader(new FileReader("FileToRead.txt"));
               //create and load a LinkedList to keep track of all threads
               LinkedList threads = new LinkedList();
               Thread curThread;
               for (int i = 0; i < numThreads; i++){
                    curThread = new Sample(String.valueOf(i));
                    synchronized (threads){
                         threads.add(curThread);
                    curThread.start();
               System.out.println("Threads started, reading file...");
               Iterator it = threads.iterator();
               //wait for all threads to die before closing the shared resources
               while (it.hasNext()){
                    ((Thread)it.next()).join();     
          catch(Exception ex){
               ex.printStackTrace();
          //close all resources
          finally{
               closeResources();
     public Sample(String threadId) throws Exception{
          super(threadId);
          Class.forName("oracle.jdbc.driver.OracleDriver");
          con = DriverManager.getConnection(url, dbUser, dbPass);
          con.setAutoCommit(false);
     public void run(){
          String line;
          int wDimId = -1, sDimId = -1, tDimId = -1, iDimId = -1;
          int abcd;
          String efgh, ijkl, mnop, cFlg = "N";
          try{
               cs = con.prepareCall("{call my_wrapper_prc(?,?,?,?,?,?,?,?,?)}");
               //read first line
               synchronized (br){
                    line = br.readLine();
               while (line != null){
                              abcd = Integer.parseInt(line.substring(0,4).trim());
                    efgh = line.substring(31,36).trim();
                    ijkl = line.substring(36,42).trim();
                          mnop = line.substring(24,31).trim();
                          cs.setInt(1, abcd);
                          cs.setString(2, efgh);
                          cs.setString(3, ijkl);
                          cs.setString(4, mnop);
                    cs.setInt(5, wDimId);
                    cs.setInt(6, tDimId);
                    cs.setInt(7, iDimId);
                    cs.setInt(8, sDimId);
                    cs.setString(9, cFlg);
                    cs.registerOutParameter(5, java.sql.Types.INTEGER);
                    cs.registerOutParameter(6, java.sql.Types.INTEGER);
                    cs.registerOutParameter(7, java.sql.Types.INTEGER);
                    cs.registerOutParameter(8, java.sql.Types.INTEGER);
                    cs.registerOutParameter(9, java.sql.Types.VARCHAR);
                    cs.executeUpdate();
                    wDimId = cs.getInt(5);
                    tDimId = cs.getInt(6);
                    iDimId = cs.getInt(7);
                    sDimId = cs.getInt(8);
                    cFlg = cs.getString(9);
                    cs.clearParameters();
                    * Logic to deal with DimId's
                    //read next line
                    synchronized (br){
                         line = br.readLine();
          // if an exception occurs, let the thread die but don't exit the application
          catch(Exception ex){
               ex.printStackTrace();
          finally{
               //close connection and CallableStatement objects
               try{
                    if (cs != null) cs.close();
                    if (con != null && !con.isClosed()) con.close();
               catch(SQLException ex){
                    ex.printStackTrace();     
     private static void closeResources(){
          //Close IO resources
}