Connection pool utilization - questions and problems.

Hi,
This is in context to JSP/Java/JPDK based web provider applcation. Appreciate it if anyone can add any input here -
1)After adding dbPersonalization to my JSP portlets I noticed that the connections in my connection pool have maxed out. After the first few page renderings, it breaks. I am not sure if its an inherent problem in my design. But, I do know that it started happening soon after I add the dbPersonalization with all its required setups as specified. Could that be possible ? Besides the connectionmanager.xml file required by the dbPersonalization setup, I also have my own connection properties file where I specify the min and max connections in the pool for all my java classes/methods to make use of. Is there a chance that the connection pooling information from both the files are clashing each other ??
2) On a related topic - I wanted to get some input on a design question. I have about 10 JSP Portlets on each of the four tabs of my Portal page, with each one instantiating one class (useBean) that contain methods to get data from the database. Now every single method of each of these classes, gets and puts a connection object from the pool.
The question is if the frequency of getting a conn object in every method of every JSP portlet too expensive ? Would it be better to make use of one connection object common to all the methods in a class/JSP/portlet ?
I had set the min to 6 and the max conns to 25 and it looks like very soon all 25 gets used, which wasnt happening before I added the dbPersonalization setup to my portlets. The dbPersonalizaiton is only for editDefaults though.
regards
-Ananth Makaram

Ryan,
as to your 7.2.1 problem: MANY people had that same issue and did revert to
7.1.1 (I did the same after being unable to connect once I upgrade) So no
worries - your AEBS is fine as it is working with 7.1.1
For the second part, I am not a wifi guy, but check out the article on
http://www.bbwexchange.com/pubs/2006/09/20/page1397-228167.asp
maybe that will give you some idea about WiFi 2.0 and if you benefit from it!
Joerg

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[email protected] (Olaf Foellinger) wrote:
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Message was edited by: Kutch'a

Hi marielouise -
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Hello everyone,
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Background...
Using Windows Vista and Flash CS5;
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thank you...
kmrproduction2

How did you solved, I have tried everything nothing works. My app id is 83TUF2RQRE.com.company_name.appstest, the screen from apple iOS Provisioning Portal -> App ID looks like this.....
Descriptions
Apple Push Notification service
In App Purchase
83TUF2RQRE.com.company_name.appstest
testapp
Configurable for Development
Configurable for Production
Enabled
I don´t know how to use it...... I'm working on WIN7 Flash CS5, I got an Ipad where i have to test a really simple app, and i cannot get installed cause of "entitlements issue". Ca Some one give a Hand on this one....
Thanks.....

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Has anyone else noticed this with 7.2.1? I hope so, or else my router is failing...
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Message was edited by: rpeters83

Ryan,
as to your 7.2.1 problem: MANY people had that same issue and did revert to
7.1.1 (I did the same after being unable to connect once I upgrade) So no
worries - your AEBS is fine as it is working with 7.1.1
For the second part, I am not a wifi guy, but check out the article on
http://www.bbwexchange.com/pubs/2006/09/20/page1397-228167.asp
maybe that will give you some idea about WiFi 2.0 and if you benefit from it!
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First of all I'd like to say Interactive Report is a really really brilliant feature, it covers exactly that points which we were missing in previous releases of Apex. Only this single feature makes Apex 3.1 release most significant for us since may be HTML DB 1.6. So much much thanks!
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is absolutelly perfect
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Message was edited by:
MAdelfio

Good day! My question and problem is, it's not secured to to download an apps because my account was hacked when I signed to Dropbox yesterday in my purchased- AlwaysOnPC Xform computing, and he/she got to me a .99$ on fb upload unlimited?

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I use drop box, remote desktop and other things, the secret is to create complex passwords and also make passwords different for each login. so if you had a password on itunes say 1tUnes## do not use this anywhere else.
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Hi to all, i have a simple question fo you (i hope that's simple :D )
I have a p4 3.2 GHz like you can see here:
FSB is 200Mhz and it's ok
But i have 4 pc3200 ram modules in dual channel mode, i think that their frequency must be 200Mhz but it's only 160, and i can't activate pat, like yuo can see here:
Now my question is: Why?
Thank to all

Quote
Originally posted by NovJoe
Simple, as displayed in the second picture, you've set your DRAM Frequency to DDR 333MHz which will be detected as 320MHz for FSb 800MHz CPU on DDR 400MHz RAMs. Due to this, CPU-Z will think that you are running in 5:4 ratio instead of 1:1 ratio. To obtain 1:1 ratio, you must set your DRAM Frequency to 400MHz in BIOS and make sure that DDR Clock is reading it at 400MHz also before saving to CMOS. Check with CPU-Z again and you'll see that it'll display 200MHz(RAMs are double rated where you've to multiply the rates by 2) and ratio at 1:1.
Isn't so easy...
My actual configuration:
Dynamic Overclocking: Private
Performance Mode: Slow (If i put fast or greater... KABOOM :D)
CPU Ratio: Locked
DRAM Frequency: 400Mhz
Spread Spectrum: Disabled
Adjust CPU Bus Clock(Mhz): 200
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CPU Vcore Adjust: NO
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In regards to every PayPal question and problem. You will not be able to switch your billing preference to PayPal unless you do it on a COMPUTER. It will never work, EVER, on an iPad. I state this from personal experience. Apparently no one in Support kno

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Judi

Thank you! I put some self help hypnosis tracks to listen to on my iPod. I did not want to go to the next track automatically, I wanted to listen to them individually, one at a time. (If I fell asleep, I did not want to 'wake up' in the middle of a different track.) Your information helps me understand that I need to re-load this playlist onto my iPod from my Mac computer, only first, I need to UNCHECK the boxes in front of each track so the iPod will STOP each time after playing the selected track. It is too bad that so many functions are not availabvle within the iPod, but that is probably why they can make it so compact.

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ResourceBundle rb = ResourceBundle.getBundle("LocalStrings");
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public static String cattrs = null;
public static String guidesearchlist[] = {};
public static int isLocalAddr = 0;
private int aeCtr;
private String[] sgDNArray;
private HashMap sgDN2DNLabel = new HashMap();
private HashMap sgDN2SearchGuide = new HashMap();
private String strport;
private int ldapport;
private String ldaphost;
private String ldapbinddn;
private String ldapbindpw;
private String ldapbasedn;
private int maxsearchcontainers;
private int maxsearchkeys;
private String guidesearchbases;
private String guidecontainerclass;
private String strlocaladdr;
private String providerurl;
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// pool and then retrieve menu data
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super.init(config);
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maxsearchcontainers = Integer.parseInt(strconts);
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maxsearchkeys = Integer.parseInt(strkeys);
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ldapbinddn = config.getInitParameter("ldapbinddn");
ldapbindpw = config.getInitParameter("ldapbindpw");
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guidesearchbases = config.getInitParameter("guidesearchbases");
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strlocaladdr = config.getInitParameter("localaddrs");
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Hashtable env = new Hashtable(11);
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env.put(Context.PROVIDER_URL, providerurl.toString());
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try {
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ctls.setSearchScope(SearchControls.SUBTREE_SCOPE);
String attrlabelkey;
sgDNArray = new String[guidesearchlist.length];
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// the dynamic menus from the result
DirContext ctx = new InitialDirContext(env);
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I get a compile error:
WhitePages.java:164: cannot resolve symbol
symbol : method search (java.lang.String,java.lang.StringBuffer,javax.naming.directory.SearchControls)
location: interface javax.naming.directory.DirContext
NamingEnumeration results = ctx.search(guidesearchlist[i], filter, ctls);
^
WhitePages.java:225: cannot resolve symbol
symbol : variable ctx
location: class OpenDirectory
ctx.close();
^
Can anyone help? If there is someone out there with JNDI connection pool experience I would appreciate your assistance!

Manish
The issue may not be related to the number of connections or the initial
connections. Check your heap size (ms, mx). Turn on verbosegc. Your heap may
not be big enough to accept the 25,000 rows.
Bernie
"Manish Kumar Singh" <[email protected]> wrote in message
news:3e6c34ca$[email protected]..
We are creating the result set with 25000 rows(each row has 56 columns) bygetting the connection using data source. With the initial capacity of the
connection pool is 5 and the max capacity as 30 and grow connection as 1,
the server gets out of memory exception, when we issue a new request, even
after closing the previous connections.
Now, if we change the initial capacity to 1 and rest all the things assame, the issue gets resolved and the server works fine.
Could you please help me out in this regard????
thanks in advance
manish

Questions regarding Connection Pooling

Hi
i have some confusion regarding how connection pooling is implemented..i have been doing some digging in to this lately but the more i read the more confused i get. i have some doubts here, will any of the posters here kindly clear them
a. Do i have to connect to my database via the DataSource method to take advantage of the connection pooling provided by my app server?..i have read conflicting information about this suggesting that Connection Pooling will not be provided to my app if i use DriverManager.getConnection()
b. if i chose to use the DataSource method do i have to implement the ConnectionPoolDataSource interface to provide the connection pooling for my app?
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Thanx

DriverManager.getConnection() literally creates, that is, builds a connection to the database using the values you previously supplied when you loaded the driver.
A connection pool is an object that contains several already made connections to the database, and simply provides you with one of those existing connections. The confusion arises because a) the method name is frequently the same and b) the connection pool object calls the driver's getConnection() method to create several connections before lending any of them out.
In other words:
DriverManager.getConnection() builds a connection to the database.
ConnectionPool.getConnection() fetches an existing connection.
So, to answer your questions...
A. This is correct. If you use DriverManager.getConnection(), you are indeed bypassing the Connection Pool entirely.
B. I'm not familiar with DataSource specifically, but in general, a third party connection pool will either give you the interface (and you implement the details) or they will give you the class file containing the DataSource object. All you would have to do in the latter case is to import that file, then create a new instance of it using the new keyword ( DataSource foo = new DataSource(); ). I suspect DataSource is indeed the class file.
C. Creating a connection pool is trivial and there are many examples of it - search on this forum or check out your favorite Java/JDBC programming book. Usually, the question "Should I use a connection pool and why?" is a more important question.

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org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'
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<resource-ref>       <description>DB Connection</description>       <res-ref-name>jdbc/phonebook_db</res-ref-name>       <res-type>javax.sql.DataSource</res-type>       <res-auth>Container</res-auth>   </resource-ref>
And this is my servlet class :
package org.DB; import javax.servlet.*; import javax.servlet.http.*; import java.io.*; import java.sql.*; import javax.naming.*; import javax.sql.*; public class TestDB2 extends HttpServlet { private Connection conn ; private Statement stat ; private ResultSet rs ; private int counter; private Object rsValue; public void init() {     try {             InitialContext ctx = new InitialContext();             DataSource ds = (DataSource)ctx.lookup("java:comp/env/jdbc/phonebook_db");             conn = ds.getConnection();             }         catch(Exception e) {               e.printStackTrace();         }     }     public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {         try {           stat = conn.createStatement();           rs = stat.executeQuery("SELECT * FROM phones_table");            } catch (SQLException sqle) {         sqle.printStackTrace();         }      response.setContentType("text/html; charset=utf-8");     PrintWriter out = response.getWriter();         String docType = "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 " + "Transitional//EN\">\n";     out.println(docType +"<HTML>\n" + "<HEAD><TITLE>PhoneBook entries</TITLE></HEAD>\n");         counter = 0;     try {         while (rs.next()) {             out.println("<h4>Entry no. " + (++counter) + "</h4>");             out.println("<table width=\"75%\" border=\"1\">");             out.println("<tr>\n"+ "<td width=\21%\"><b>LastName:</b></td>\n"+ "<td width=\"79%\">");             out.println((((rsValue = rs.getObject("LASTNAME"))==null || rs.wasNull())?                 "":(rsValue.toString())));             out.println("</td>\n</tr>\n" + "<tr>\n"+                     "<td width=\21%\"><b>FirstName:</b></td>\n"+ "<td width=\"79%\">");             out.println((((rsValue = rs.getObject("FIRSTNAME"))==null || rs.wasNull())?                 "":(rsValue.toString())));             out.println("</td>\n"+ "</tr>\n"+                     "<td width=\21%\"><b>Phone:</b></td>\n"+ "<td width=\"79%\">");             out.println((((rsValue = rs.getObject("PHONE"))==null || rs.wasNull())?                 "":(rsValue.toString())));             out.println("</td>\n" + "</tr>\n" +                     "</table>\n"+ "<br>\n<br>");         }     } catch (SQLException sqle) {         sqle.printStackTrace();     }     out.println("</body>\n"+             "</html>"); } public void destroy() {     try {         rs.close();         stat.close();         conn.close();     } catch (SQLException sqle) {         sqle.printStackTrace();         }     } }{code} Any suggestions?

Thank you for your answer.Yes my servlet class is something more worse than horrible(i don't use the database connection correct i don't use the MVC pattern i use out.println() ) but i just tried to take a ready example and try to understand .So i write this servlet myself as a starting point :
package org.DB;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.sql.*;
public class DBServlet extends HttpServlet {
    private Connection conn ;
    private Statement stat ;
    private ResultSet rs ;
    private int counter;
    String driver = "com.mysql.jdbc.Driver";
    String dbURL = "jdbc:mysql://localhost:3306/phonebookdb?user=**********&password=************";
    @Override
public void init() {
     try {
            Class.forName(driver).newInstance();
            conn = DriverManager.getConnection(dbURL);
     }catch(Exception e) {
              e.printStackTrace();
              System.err.print("Unable to make connection ");
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            out.println("<html>");
            out.println("<head>");
            out.println("<title>Servlet DBServlet</title>");
            out.println("</head>");
            out.println("<body>");
            out.println("<h1>Servlet DBServlet at " + request.getContextPath () + "</h1>");
            out.println("<br /><br /><br />");
            if(conn!=null)
                out.println("conn object : "+conn);
            out.println("</body>");
            out.println("</html>");
        } catch(Exception sq) {
            System.out.println("Exception" + sq.getMessage());
            out.close();
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
     public void destroy() {
     try {
         conn.close();
     } catch (SQLException sqle) {
         sqle.printStackTrace();
    @Override
    public String getServletInfo() {
        return "A Simple Servlet";
}And it work for now.
Edited by: pavlos555 on Oct 21, 2008 10:21 AM

Connection pool utilization - questions and problems.

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