Performance Tuning Siebel Software on the Sun Platform

the database during peak load. In the <strong>Siebel</strong> tests this was about 80 during a 10,000 user
test.
The size of each rollback segment should be approximately equal to the size in bytes of a
user transaction. For the <strong>Siebel</strong> workload 100 rollback segments of 20Mbytes with extent
size of 1Mbyte was found suitable. Note: If the rollback segment sizing is larger than
required by the application, one would end up wasting valuable space in the database
cache.
The new feature from oracle UNDO Segments, which can be used instead of Rollback
Segments, was not tested during this project with <strong>Siebel</strong> application.
7.6.10 Database Connectivity Using Host Names Adapter
It has been observed that high-end <strong>Siebel</strong> test runs using Oracle as the backend have
performed better when client-to-Oracle server connectivity is done via the hostnames
adapter feature. This is an Oracle feature that allows for an alternate method of
connecting to the Oracle database server without using the tnsnames.ora file.
Set the GLOBAL_DBNAME to something other than the Oracle_SID in the
Listener.ora file on the database server as shown below. Bounce the Oracle listener
after making this change.
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC))
)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = dbserver)(PORT = 1521))
)
)
(DESCRIPTION =
(PROTOCOL_STACK =
(PRESENTATION = GIOP)
(SESSION = RAW)
)
(ADDRESS = (PROTOCOL = TCP)(HOST = dbserver)(PORT = 2481))
)
)
SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(SID_NAME = PLSExtProc)
(ORACLE_HOME = /export/pspp/oracle)
(PROGRAM = extproc)
)
(SID_DESC =
(GLOBAL_DBNAME = oramst.dbserver)
(ORACLE_HOME = /export/pspp/oracle)
(SID_NAME = oramst)
<strong>Performance</strong> <strong>Tuning</strong> <strong>Siebel</strong> <strong>Software</strong> on the Sun Platform Page 53