A Simple Way To Find Which process Is Taking Big Swap

Run top then press 'O' (capital letter o) followed by 'p' then 'enter'. Now processes should be sorted by their swap usage.

How To Debug DataGuard broker dgmgrl ORA-16664

After you setup dg broker in your enviroment, all TNS are correct, ports are open, sqlplus sys as sysdba is fine. password file are identical. You still see below error on DRC logs

ORA-16664: unable to receive the result from a database

Reason:

   It is possible dg broker ignore the changes you made on tnsnames.ora. It stores its own connect string when you set up dg broker at the beginning

Solution:

   Turn on trace to support .
   dgmgrl>EDIT CONFIGURATION set property tracelevel=support;
   dgmgrl>EDIT INSTANCE "COMMPRDA1" ON DATABASE COMMPRDA set property LogArchiveTrace=8191;

   Find out exact connect string it is using via drc logs. Test the string on sqlplus

   In my case, the special listener we created before for dataguard which confuses dg broker to create its own connect string. Fix it via update your listener.ora

  Or staticconnectidentifier
  dgmgrl>edit instance 'CONTNTA1' on database contntadc set property staticconnectidentifier='TNS string';

 Turn off trace.
dgmgrl>EDIT CONFIGURATION set property tracelevel=user;
dgmgrl>EDIT INSTANCE "COMMPRDA1" ON DATABASE COMMPRDA set property LogArchiveTrace=0;

A simple command to check which process takes OS memory in linux

ps -e -orss=,args= | sort -b -k1,1n | pr -TW$COLUMNS