Memory leak in weblogic 6.0 sp2 oracle 8.1.7 thin driver

Question

Hi,
     I have a simple client that opens a database connection, selects from
a table containing five rows of data (with four columns in each row)
and then closes all connections. On running this in a loop, I get the
following error after some time:
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Adapter>
<OutOfMemoryError in
Adapter
java.lang.OutOfMemoryError
<<no stack trace available>>
>
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Kernel> <ExecuteRequest
failed
java.lang.OutOfMemoryError
I am running with a heap size of 64 Mb. The java command that runs
the client is:
java -ms64m -mx64m -cp .:/opt/bea/wlserver6.0/lib/weblogic.jar
-Djava.naming.f
actory.initial=weblogic.jndi.WLInitialContextFactory
-Djava.naming.provider.url=
t3://garlic:7001 -verbose:gc Test
The following is the client code that opens the db connection and does
the select:
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
public class Test {
private static final String strQuery = "SELECT * from tblPromotion";
public static void main(String argv[])
throws Exception
String ctxFactory     = System.getProperty
("java.naming.factory.initial");
String providerUrl     = System.getProperty
("java.naming.provider.url");
Properties jndiEnv          = System.getProperties ();
System.out.println ("ctxFactory : " + ctxFactory);
System.out.println ("ProviderURL : " + providerUrl);
Context ctx     = new InitialContext (jndiEnv);
for (int i=0; i <1000000; i++)
System.out.println("Running query for the "+i+" time");
Connection con = null;
Statement stmnt = null;
ResultSet rs     = null;
try
DataSource ds     = (DataSource) ctx.lookup
(System.getProperty("eaMDataStore", "jdbc/eaMarket"));
con = ds.getConnection ();
stmnt = con.createStatement();
rs = stmnt.executeQuery(strQuery);
while (rs.next ())
//System.out.print(".");
//System.out.println(".");
ds = null;
catch (java.sql.SQLException sqle)
System.out.println("SQL Exception : "+sqle.getMessage());
finally
try {
rs.close ();
rs = null;
//System.out.println("closed result set");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
stmnt.close ();
stmnt = null;
//System.out.println("closed statement");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
con.close();
con = null;
//System.out.println("closed connection");
} catch (Exception e) {
System.out.println("Exception closing connection");
I am using the Oracle 8.1.7 thin driver. Please let me know if this
memory leak is a known issue or if its something I am doing.
thanks,
rudy

Answer 1

Repost in JDBC section ... very serious issue but it may be due to Oracle or
to WL ... does it happen if you test inside WL itself?
How many iterations does it take to blow? How long? Does changing to a
different driver (maybe Cloudscape) have the same result?
Peace,
Cameron Purdy
Tangosol Inc.
<< Tangosol Server: How Weblogic applications are customized >>
<< Download now from http://www.tangosol.com/download.jsp >>
"R.C." <[email protected]> wrote in message
news:[email protected]...
Hi,
I have a simple client that opens a database connection, selects from
a table containing five rows of data (with four columns in each row)
and then closes all connections. On running this in a loop, I get the
following error after some time:
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Adapter>
<OutOfMemoryError in
Adapter
java.lang.OutOfMemoryError
<<no stack trace available>>
>
<Nov 28, 2001 5:57:40 PM GMT+06:00> <Error> <Kernel> <ExecuteRequest
failed
java.lang.OutOfMemoryError
I am running with a heap size of 64 Mb. The java command that runs
the client is:
java -ms64m -mx64m -cp .:/opt/bea/wlserver6.0/lib/weblogic.jar
-Djava.naming.f
actory.initial=weblogic.jndi.WLInitialContextFactory
-Djava.naming.provider.url=
t3://garlic:7001 -verbose:gc Test
The following is the client code that opens the db connection and does
the select:
import java.util.*;
import java.sql.*;
import javax.naming.*;
import javax.sql.*;
public class Test {
private static final String strQuery = "SELECT * from tblPromotion";
public static void main(String argv[])
throws Exception
String ctxFactory = System.getProperty
("java.naming.factory.initial");
String providerUrl = System.getProperty
("java.naming.provider.url");
Properties jndiEnv = System.getProperties ();
System.out.println ("ctxFactory : " + ctxFactory);
System.out.println ("ProviderURL : " + providerUrl);
Context ctx = new InitialContext (jndiEnv);
for (int i=0; i <1000000; i++)
System.out.println("Running query for the "+i+" time");
Connection con = null;
Statement stmnt = null;
ResultSet rs = null;
try
DataSource ds = (DataSource) ctx.lookup
(System.getProperty("eaMDataStore", "jdbc/eaMarket"));
con = ds.getConnection ();
stmnt = con.createStatement();
rs = stmnt.executeQuery(strQuery);
while (rs.next ())
//System.out.print(".");
//System.out.println(".");
ds = null;
catch (java.sql.SQLException sqle)
System.out.println("SQL Exception : "+sqle.getMessage());
finally
try {
rs.close ();
rs = null;
//System.out.println("closed result set");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
stmnt.close ();
stmnt = null;
//System.out.println("closed statement");
} catch (Exception e) {
System.out.println("Exception closing result set");
try {
con.close();
con = null;
//System.out.println("closed connection");
} catch (Exception e) {
System.out.println("Exception closing connection");
I am using the Oracle 8.1.7 thin driver. Please let me know if this
memory leak is a known issue or if its something I am doing.
thanks,
rudy