Problem to download a file from 2 browsers at the time

I have this JSP that download an excel file.

It works fine if I use only one browser at the same time.

The problem is when I try to do this but from 2 browsers at the same
time. From each browser I can download a part of the file but not the
complete file.
It seems the browsers are sharing the bandwidth and when it starts to
download a file the other stops.

I have look the logs, and I saw the file has downloaded to the computer

and while the the jsp is working.
I don't undestand why the file has finished to download and while the
jsp is still executing.

Can you help me please?

do anybody try this JSP and tell me if the result is the same as me?

------------------------------------------JSP
-----------------------------------------------------------------------------------

<%@page contentType="application/vnd.ms-excel"%>

<%@ page language="java" import="java.io.*"%>
<%@ page language="java" import="java.util.*"%>

<%

Date fecha = new Date();

java.sql.Date fechaSQL = new java.sql.Date(fecha.getTime());

Calendar calendario = Calendar.getInstance();
calendario.setTime(fecha); // fecha es el Date de antes.
String strHour = String.valueOf( calendario.get(Calendar.HOUR) );
String strMinute = String.valueOf( calendario.get(Calendar.MINUTE) );
String strSecond = String.valueOf( calendario.get(Calendar.SECOND) );

String nombre = "FILE" + strHour + strMinute + strSecond + ".xls";

 System.out.println( " IN OF " + nombre );

     response.setContentType( "application/x-download" );

     response.setHeader("Content-type","application/vnd.ms-excel");

     response.setHeader("Content-Disposition","attachment; filename=\""
+ nombre + "\"");

 System.out.println( nombre + " START" );

for (int l=0;l<30000;l++){
 System.out.println( nombre + " " + l );

  for (int k=0;k<250;k++){

        out.write(nombre + " : ("+ l + "," + k + ")" + "\t" );

  }
        out.write("\n");

}

 System.out.println( nombre + " END" );

%>