Wt

Hi

*I'm using WT3.2.3, boost 1.52 and postgres db(8.4) - all in multi-threaded server.

Till now I used:*

dbo::backend:Postgres connection(Singleton::Instance().database());

session->setConnection(connection);

*for each session for connect to the database, but now I want to use connection pool.

So I prepared some classes:*

class DboFixture

{

public:

DboFixture(){}

void initializeConnectionPool() {

dbo::SqlConnection* connection = new dbo::backend::Postgres(Singleton::Instance().database());

connectionPool_ = new dbo::FixedSqlConnectionPool(connection, Singleton::Instance().postgresPool());

};

~DboFixture() {

delete connectionPool_;

};

dbo::SqlConnectionPool& getConnectionPool(){

return *connectionPool_;

}

private:

dbo::SqlConnectionPool *connectionPool_;

};

• and main.cpp looks like:*

DboFixture pgConnectionPool;

class SongWWWApplication : public WApplication

{

public:

SongWWWApplication(const WEnvironment& env)

: WApplication(env)

{

root()->addWidget(new MainView("/"));

#ifdef ENABLE_STATSD_MONITORING

Monitor_Gauge("server","sessions",sessionNumber());

#endif

}

~SongWWWApplication()

{

#ifdef ENABLE_STATSD_MONITORING

Monitor_Gauge("server","sessions",sessionNumber());

#endif

}

};

WApplication* createApplication(const WEnvironment& env)

{

return new SongWWWApplication(env);

}

int main(int argc, char argv) {

std::string settings_file;

try {

WServer server(argv[0]);

server.setServerConfiguration(argc, argv, WTHTTP_CONFIGURATION);

Singleton::Instance().readConfiguration("settings.xml");

pgConnectionPool.initializeConnectionPool();

server.addEntryPoint(Application, createApplication, DefaultEntryPointStr);

if (server.start()) {

int sig = WServer::waitForShutdown(argv[0]);

std::cerr << "Shutdown (signal = " << sig << ")" << std::endl;

server.stop();

if (sig == SIGHUP) {

std::cerr << "\nReread configuration: settings.xml\n";

WServer::restart(argc, argv, environ);

}

}

}

catch (WServer::Exception& e) {

std::cerr << e.what() << "\n";

return 1;

}

catch (std::exception& e) {

std::cerr << "exception: " << e.what() << "\n";

return 1;

}

return 0;

}

MainSession is member of MainView class:

class MainSession : public dbo::Session

{

public:

MainSession(dbo::SqlConnectionPool& connectionPool);

void setUser(dbo::ptr user);

dbo::ptr user() const { return user_; }

private:

dbo::ptr user_;

};

MainSession::MainSession(dbo::SqlConnectionPool& connectionPool)

{

setConnectionPool(connectionPool);

mapClass("user");

...

};

and is initialized like:

extern DboFixture pgConnectionPool;

MainView::MainView(const std::string& basePath)

: m_base_path(basePath), m_session(pgConnectionPool.getConnectionPool())

{

...

};

I tested my web app with "https://strucr.com" crawler (4-12 threads with no delay between request) and with old connection to db everythink was ok, but with connection pool I had very offten deadlock (server not responding) or segmentation false.

deadlock:

threads - http://screencast.com/t/DkYhNcLr6TW

thread (_lll_lock_wait) - http://screencast.com/t/kx3HOoGy

rest threads (*Gl_pool) looks similar - http://screencast.com/t/mVk3Plr7Y

*What is the best way to initialize each session with connection pool?

If needed I can give more information.*

*best regrads

Musicplayr*

PS. I'm sorry for duplicated http://redmine.webtoolkit.eu/issues/1672