OCCI Threading - core dumps

Question

Hi,
After learning howto setup my OCCI Environment handle
correctly for threads using;
Environment::Mode mode = (Environment::THREADED_MUTEXED,
Environment::OBJECT);
The class that encapsulates this is a singleton and used
through out the process by all the threads. This class
conection pools and is synchronised for all the threads.
However, using this singleton model, I get core dumps
when more than 1 thread attempts to execute a commit on
the database via the connection they have obtained from
this singleton class.
Instantiating the class or environment per thread does
not result in core dumps. Rather it runs smoothly.
Is this normal behaviour?
(Also when all the threads are querying the singleton
model works fine. Seems only commits)
Raffaele

Answer 1

Hi,
I tried the THREADED_MUTEX|OBJECT but I still get core
dumps when threading. What I experience is during a
connection->commit() or any other call on a connection
when threading causes a core dump.
I use the OCCI object inrterface and my db is an object
schema. I am trying to use the full OO dev that comes
with Oracle...ott included.
Everything boils down to my singleton DB class which
is shown below; (Is there any other thread initialisation
required)
#include <db/oracle.h>
#include <env/config.h>
#include <env/errlog.h>
#include <env/stdenv.h>
#include <taucpp/except_base.h>
#include <gtcpp/mtlock.h>
#include <gtcpp/debug.h>
GTFILE;
static GtMtCritSec db_mutex;
Oracle::Oracle (GtString &userName,
GtString &password,
GtString &url,
int max,
int min,
int inc) :
_user (userName),
_pwd (password),
_url (url),
_max (max),
_min (min),
_inc (inc),
_connection (0)
GtMtAutoLock lock (db_mutex);
Environment::Mode mode
= (Environment::Mode) (Environment::THREADED_MUTEXED | Environment::OBJECT);
_system = Environment::createEnvironment (mode);
char* s = getenv ("ORACLE_HOME");
if (!s || (strlen (s) == 0))
cout << "environment variable ORACLE_HOME not initialized"
<< endl;
connect ();
Oracle::~Oracle ()
GtMtAutoLock lock (db_mutex);
if (_connection)
system->terminateConnectionPool (connection);
Environment::terminateEnvironment (_system);
void Oracle::getConnection (Connection** connection)
GTASSERT (connection);
GtMtAutoLock lock (db_mutex);
try
if (_connection)
*connection = connection->createConnection ( (char*)& (*user),
(char*)& (*_pwd));
else
Exception ex ("MSN reconnect exception");
*connection = 0;
throw ex;
catch (SQLException ex)
retry ();
catch(Exception ex)
retry();
catch (...)
void Oracle::retry ()
GtMtAutoLock lock (db_mutex);
try
if (_connection)
system->terminateConnectionPool (connection);
catch (...)
connect ();
void Oracle::terminateConnection (Connection* connection)
GTASSERT (connection);
GtMtAutoLock lock (db_mutex);
if (connection)
try
if (_connection)
_connection->terminateConnection (connection);
catch (SQLException ex)
catch (...)
Environment* Oracle::getEnvironment ()
GtMtAutoLock lock (db_mutex);
return _system;
void Oracle::connect ()
GtMtAutoLock lock (db_mutex);
try
connection = system->createConnectionPool ( (char*)& (*_user),
(char*)& (*_pwd),
(char*)& (*_url),
min,max,_inc);
catch (SQLException ex)
_connection = 0;
catch (...)
_connection = 0;
Any help much appreciated,
Raffaele