DATAPUMP with SYS$SYS.* service_names

While we using DATAPUMP, we will find ALTER SYSTEM SET service_names='SYS$SYS.*...' in alert log file(RAC).

$ expdp directory=TMP logfile=full.log dumpfile=full.dmp full=y

In alert log file:
Mon Nov 30 01:14:22 2009
ALTER SYSTEM SET service_names='service2','service1','SYS$SYS.KUPC$C_1_20091130011411.ORCL' SCOPE=MEMORY SID='orcl1';
ALTER SYSTEM SET service_names='SYS$SYS.KUPC$C_1_20091130011411.ORCL','service2','service1','SYS$SYS.KUPC$S_1_20091130011411.ORCL' SCOPE=MEMORY SID='orcl1';
Mon Nov 30 01:14:29 2009
DM00 started with pid=56, OS id=26976, job SYS.SYS_EXPORT_SCHEMA_01

At "SERVICE_NAMES" parameter:

SQL> show parameter service_names

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
service_names string SYS$SYS.KUPC$C_1_20091130011411.ORCL, service2, service1, SYS$SYS.KUPC$S_1_20091130011411.ORCL

After DATAPUMP finished. In alert log file:

ALTER SYSTEM SET service_names='SYS$SYS.KUPC$S_1_20091130011602.ORCL','service2','service1' SCOPE=MEMORY SID='orcl1';
ALTER SYSTEM SET service_names='service2','service1' SCOPE=MEMORY SID='orcl1';

At SERVICE_NAMES parameter:

SQL> show parameter service_names

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
service_names string service2, service1

DATAPUMP doesn't change existing service name and no impact to existing services.
DATAPUMP just adds new services for its own queue operation.

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