SOA11g Datasource has been suspended.

Problem:
 Pool xyz_db_ds is Suspended, cannot allocate resources to applications

Summary:
This happens when the database has no more free connections, the datasource connection pool keeps requesting them, and weblogic suspends it.

Solution:
To resolve this exception, ask your DBA to give you a report about you database load, or, if you have a sysdba account, just run these commands:

Run these commands

--see current sessions/processes:
select count(*) from v$process;
select count(*) from v$session;

--see database configuration:
select *  from v$parameter where name in ('sessions','processes','transactions');

Increase the connections or correctly dimension your datasource connection pool to match the free sessions

sql> alter system set processes=500 scope=spfile sid='*';
sql> alter system set sessions=555 scope=spfile sid='*';
sql> alter system set transactions=610 scope=spfile sid='*';
sql> shutdown immediate
sql> restart

Finally , on the weblogic server reset this  datasource.

References:
http://egherardini.wordpress.com/2011/04/27/oracle-soa-suite-11g-datasource-has-been-suspended/