Real-time apply in Maximum Performance Mode Not Working

Question

We have configured physical standby database in maximum performance mode. It's working perfectly fine. Archive logs are being applied to the physical standby.
We can open the DB in read-only mode, but real-time apply is not working. Physical standby database is lagging behind the primary db by an archive log. As soon as primary database generates an archive log, it's transported over to the standby and applied immediately by the media recovery process. But real-time redo is not working. Standby redo logs have been configured.
On Physcial Standby:
SQL> alter database recover managed standby database using current logfile disconnect ;
Database Altered.
SQL> select group#, DBID, status,first_time, last_time from v$standby_log ;
GROUP# DBID STATUS FIRST_TIM LAST_TIME
4 UNASSIGNED UNASSIGNED
5 UNASSIGNED UNASSIGNED
6 UNASSIGNED UNASSIGNED
7 UNASSIGNED UNASSIGNED
SQL> select * from v$dataguard_stats ;
NAME
VALUE
UNIT TIME_COMPUTED
apply lag
+00 00:31:36
day(2) to second(0) interval 22-JUN-2010 08:42:06
transport lag
+00 00:31:34
day(2) to second(0) interval 22-JUN-2010 08:42:06
As you could see from the output above, value of transport and apply lag is equal to the elapsed time since last archive log switch.
********* Standby init.ora
db_name = CPRD
db_unique_name = CPRDS
instance_name = CPRD
service_names = hrDBSBY.WORLD
log_archive_format = CPRD%r%s.%t
log_archive_dest_1 = "location=f:\orarch\hresysprod"
log_archive_dest_2='service=hresysprod async db_unique_name=cprd valid_for=(primary_role,online_logfile)'
log_archive_config='dg_config=(cprd,cprds)'
fal_server=hresysprod
fal_client=hresysprods
standby_file_management=auto
log_archive_trace=1
log_file_name_convert = ('hresysprod','hresysprods')
db_file_name_convert = ('hresysprod','hresysprods')
remote_login_passwordfile = exclusive
******* Primary init.ora
log_archive_config='dg_config=(cprd,cprds)'
fal_server=hresysprods
fal_client=hresysprod
standby_file_management=auto
log_archive_format = CPRD%r%s.%t
log_archive_dest_1 = "location=f:\orarch\hrESYSPROD"
log_archive_dest_2='service=hresysprods async db_unique_name=cprds valid_for=(primary_role,online_logfile)'
log_archive_trace=1
remote_login_passwordfile = exclusive
Please advise.
Thanks,
jay

Answer 1

Hi,
In your case you are using ARC process for redo transfer as you have not specified any process in log_archive_dest_2 and default is arch.
I will suggest you to use LGWR to transfer the redo to standby and also check the size of standby redo logs on standby is same to the size of online redo logs on primary
Regards
Anudeep