Also you must filter the background sessions in your query! probably a better query would be select sid from gv$session where username = 'YOUR APP USER' group by sid having count(*)>1 On 9/27/07, qihua wu <staywithpin@xxxxxxxxx> wrote: > > We have a two nodes RAC, the strange thing is that many sessions run on > both nodes. > select sid from gv$session group by sid having count(*)>1 > they are lots of rows return. > > My understanding for load balance is: if sessions on instance 1 are too > many, then new session will be connected to instance 2. > But if at the beginning there were100 sessions on both inst1 and inst2, > after all the sessions on inst2 are completed, no existing session on > instance1 will go to instance2. > > But the fact of the above query told me some sessions run on both > instance. How can this be true? > > > > >