Обсуждение: maxconnection
hi,all:
I want to constraint the maximum number of concurrent connections to 25
in postgres
jdbc driver. There are no methods for this
change. How would i do?
TIA
zhuj
You have to limit the connections on the backend, in postgresql.conf. Dave On Tue, 2003-06-17 at 05:22, zhuj wrote: > hi,all: > I want to constraint the maximum number of concurrent connections to 25 > in postgres > jdbc driver. There are no methods for this > change. How would i do? > > TIA > zhuj > > > > ---------------------------(end of broadcast)--------------------------- > TIP 3: if posting/reading through Usenet, please send an appropriate > subscribe-nomail command to majordomo@postgresql.org so that your > message can get through to the mailing list cleanly > -- Dave Cramer <Dave@micro-automation.net>
Really, what happens? I am pretty sure you won't get more than 25 connections. Dave On Thu, 2003-06-19 at 21:03, zhuj wrote: > I try to edit the postgresql.conf, set > "max_connections " to 25 then restart > postgres, but it seems not work. > > ----- Original Message ----- > From: "Dave Cramer" <Dave@micro-automation.net> > To: "zhuj" <zhuj@dragontec.com.cn> > Cc: <pgsql-jdbc@postgresql.org> > Sent: Friday, June 20, 2003 4:23 AM > Subject: Re: [JDBC] maxconnection > > > > You have to limit the connections on the backend, in postgresql.conf. > > > > Dave > > On Tue, 2003-06-17 at 05:22, zhuj wrote: > > > hi,all: > > > I want to constraint the maximum number of concurrent connections to > 25 > > > in postgres > > > jdbc driver. There are no methods for this > > > change. How would i do? > > > > > > TIA > > > zhuj > > > > > > > > > > > > ---------------------------(end of broadcast)--------------------------- > > > TIP 3: if posting/reading through Usenet, please send an appropriate > > > subscribe-nomail command to majordomo@postgresql.org so that your > > > message can get through to the mailing list cleanly > > > > > -- > > Dave Cramer <Dave@micro-automation.net> > > > > > -- Dave Cramer <Dave@micro-automation.net>
I am testing our connection pool program.
The constructor of connection pool class
shows below:
public ConnectionPool(int size, int maxSize) throws SQLException {
try {
this.size = size;
this.maxSize = maxSize;
for (int i = 0; i < this.size; i++) {
PooledConnection pooledConnection = (PooledConnection)
DataSource.this.getPooledConnection();// get connection
from postgres
if (this.connectionMemento == null)
this.connectionMemento =
pooledConnection.createConnectionMemento();
pooledConnection.addConnectionEventListener(this);
this.pool.add(pooledConnection);
}
} catch (SQLException e) {
closeAll(this.pool);
throw e;
}
}
the details of getPooledConnection() method:
public javax.sql.PooledConnection getPooledConnection() throws SQLException
{
return new PooledConnection(DriverManager.getConnection(this.url,
this.user,
this.password));
}
The test program create the ConnectionPool object:
new ConnectionPool(30, 50);
if max connection is set to 25, "new ConnectionPool(30, 50)"
should throw SQLException. But it did not. It runs normally.
----- Original Message -----
From: "Dave Cramer" <Dave@micro-automation.net>
To: "zhuj" <zhuj@dragontec.com.cn>
Cc: <pgsql-jdbc@postgresql.org>
Sent: Friday, June 20, 2003 8:58 AM
Subject: Re: [JDBC] maxconnection
> Really, what happens? I am pretty sure you won't get more than 25
> connections.
>
> Dave
> On Thu, 2003-06-19 at 21:03, zhuj wrote:
> > I try to edit the postgresql.conf, set
> > "max_connections " to 25 then restart
> > postgres, but it seems not work.
> >
> > ----- Original Message -----
> > From: "Dave Cramer" <Dave@micro-automation.net>
> > To: "zhuj" <zhuj@dragontec.com.cn>
> > Cc: <pgsql-jdbc@postgresql.org>
> > Sent: Friday, June 20, 2003 4:23 AM
> > Subject: Re: [JDBC] maxconnection
> >
> >
> > > You have to limit the connections on the backend, in postgresql.conf.
> > >
> > > Dave
> > > On Tue, 2003-06-17 at 05:22, zhuj wrote:
> > > > hi,all:
> > > > I want to constraint the maximum number of concurrent
connections to
> > 25
> > > > in postgres
> > > > jdbc driver. There are no methods for this
> > > > change. How would i do?
> > > >
> > > > TIA
> > > > zhuj
> > > >
> > > >
> > > >
> > > > ---------------------------(end of
broadcast)---------------------------
> > > > TIP 3: if posting/reading through Usenet, please send an appropriate
> > > > subscribe-nomail command to majordomo@postgresql.org so that
your
> > > > message can get through to the mailing list cleanly
> > > >
> > > --
> > > Dave Cramer <Dave@micro-automation.net>
> > >
> > >
> >
> --
> Dave Cramer <Dave@micro-automation.net>
>
>
I try to edit the postgresql.conf, set "max_connections " to 25 then restart postgres, but it seems not work. ----- Original Message ----- From: "Dave Cramer" <Dave@micro-automation.net> To: "zhuj" <zhuj@dragontec.com.cn> Cc: <pgsql-jdbc@postgresql.org> Sent: Friday, June 20, 2003 4:23 AM Subject: Re: [JDBC] maxconnection > You have to limit the connections on the backend, in postgresql.conf. > > Dave > On Tue, 2003-06-17 at 05:22, zhuj wrote: > > hi,all: > > I want to constraint the maximum number of concurrent connections to 25 > > in postgres > > jdbc driver. There are no methods for this > > change. How would i do? > > > > TIA > > zhuj > > > > > > > > ---------------------------(end of broadcast)--------------------------- > > TIP 3: if posting/reading through Usenet, please send an appropriate > > subscribe-nomail command to majordomo@postgresql.org so that your > > message can get through to the mailing list cleanly > > > -- > Dave Cramer <Dave@micro-automation.net> > >
You likely need to increase the shared_buffers to at least 2* max connections. Do you have logging of any kind turned on? If you have silent_mode set to true, set it to false and try starting the database again and look for error messages. If you've got it set to log somewhere, read the logs after trying to restart. Or by "not work" do you mean it doesn't limit the max connections properly? On Fri, 20 Jun 2003, zhuj wrote: > I try to edit the postgresql.conf, set > "max_connections " to 25 then restart > postgres, but it seems not work. > > ----- Original Message ----- > From: "Dave Cramer" <Dave@micro-automation.net> > To: "zhuj" <zhuj@dragontec.com.cn> > Cc: <pgsql-jdbc@postgresql.org> > Sent: Friday, June 20, 2003 4:23 AM > Subject: Re: [JDBC] maxconnection > > > > You have to limit the connections on the backend, in postgresql.conf. > > > > Dave > > On Tue, 2003-06-17 at 05:22, zhuj wrote: > > > hi,all: > > > I want to constraint the maximum number of concurrent connections to > 25 > > > in postgres > > > jdbc driver. There are no methods for this > > > change. How would i do? > > > > > > TIA > > > zhuj > > > > > > > > > > > > ---------------------------(end of broadcast)--------------------------- > > > TIP 3: if posting/reading through Usenet, please send an appropriate > > > subscribe-nomail command to majordomo@postgresql.org so that your > > > message can get through to the mailing list cleanly > > > > > -- > > Dave Cramer <Dave@micro-automation.net> > > > > > > > ---------------------------(end of broadcast)--------------------------- > TIP 5: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faqs/FAQ.html >