Troubleshooting 9
Troubleshooting
This section provides recommended actions for problems that you 
may encounter while deploying and using your Enterprise Linux and 
Oracle software. 
Performance and Stability
Enterprise Linux exhibits poor performance and instability; 
excessive
 use of swap space
When Oracle System Global Area (SGA) exceeds the recommended size, 
Enterprise Linux exhibits poor performance. Always ensure that the SGA size 
does not exceed 65% of the total system RAM. To decrease the SGA size:
Enter free at a command prompt to determine the total RAM and reduce 
the values of db_cache_size and shared_pool_size parameters in the Oracle 
parameter file accordingly.
Unknown interface-type warning appears in the Oracle alert file; 
poor system performance
The problem occurs when the public interface is configured as cluster 
communications (private interface). 
Perform the following steps on one node to force cluster communications to 
the private interface:
a
Log in as 
oracle
.
b
Enter 
sqlplus "/ as sysdba"
 at the command prompt. 
The
 
SQL>
 prompt appears.
c
Enter the following lines at the 
SQL>
 prompt:
alter system set cluster_interconnects=<private 
IP address node1>’ scope=spfile sid=’<SID1>’ 
alter system set cluster_interconnects =
’<private IP address node2>’ scope=spfile sid=
’<SID2>’