Fourth, MTS configuration implementation
1. Several parameters for the Oracle8i MTS environment
Serial number
parameter
Description
1 MTS_DISPATCHERS
Used to configure the number of Dispatcher, which is enabled when instance starts, and the protocol responded to Dispatcher, it is a dynamic parameter, which can be dynamically modified with ALTER SYSTEM, which has no default.
2 MTS_MAX_DISPATCHERS
The maximum number of Dispatcher processes used simultaneously, for most applications, enabling a Dispatcher to achieve better performance per 250 connections. The default is 5 or the quantity of the configured Dispatcher
3 MTS_SERVERS
Used to specify the number of service processes you want to enable when Instance starts, it is a dynamic parameter that can be dynamically modified with ALTER SYSTME. 4 MTS_MAX_SERVERS
The number of service processes used to specify simultaneous shared libraries, if your system often occurs, it should increase this value appropriate. 5 MTS_SERVICE
Set to SID 6 MTS_Listener_Address TNS listening address
2, several parameters that are commonly used in Oracle9i MTS environment
Serial number
parameter
Description
1 dispatcher
MTS_DISPATCHERS parameters equivalent to 8i
2 Max_Dispatcher
MTS_MAX_DISPATCHERS parameters equivalent to 8i
3 Shared_Servers
MTS_SERVER parameter 4 max_shared_servers equivalent to 8i
MTS_MAX_SERVERS parameters equivalent to 8i
3, take an example of an actual environment (ORACLE8.1.7.4), 9i, I added the following MTS parameters in the initial file of the init
#mps set by qiuyb
MTS_DISPATCHERS = "(PROTOCOL = TCP) (Host = 192.168.223.125)) (Dispatcher = 10)"
MTS_MAX_DISPATCHERS = 20
MTS_SERVERS = 10
MTS_MAX_SERVERS = 50
MTS_SERVICE = BILLING
MTS_Listener_Address = "(ADDRESS = (protocol = TCP) (Host = 192.168.223.125) (port = 1521))" Large_pool_size = 400m
#End of qiuyb's set
It is necessary to indicate that the LARGE_POOL_SIZE is initialized, and this parameter is set in the MTS environment, so that the UGA is allocated from a fixed area such as Large_pool without having to distribute from Shared Pool. Can reduce the occurrence of ORA-04031 errors.
5. Optimize the MTS configuration option and several questions you may ask
1, large_pool_size This parameter does I have?
When the size of the LARGE_POOL_SIZE can meet the memory required for all shared service processes, of course, if the memory is enough, it can be appropriately increased, and the following statements can be obtained from the maximum number of memory used by the instance startup MTS connection. It can be seen that it is more than 200 M.
Select SUM (Value) "Max Mts Memory Allocated"
From v $ SESSSTAT SS, V $ STATNAME ST
Where name = 'session uga memory max'and ss.statistic # = st.statistic #
Max MTS Memory Allocated
---------------------------------------------------------------------------------------------------------------------------------------
214457296
2. How do I determine that my DISPATCHER is not enough?
Using the following statement, when the busy ratio of Dispatcher exceeds 50%, you will consider adding the number of dispatcher, and the ALTER SYSTEM dynamics can be done.
Select Name, (busy / (busy idle) * 100 "Dispatcher% Busy Rate"
From v $ dispatcher
3. How do I determine whether the sharing service process is enough?
Use the following statements to determine the average wait time of each request, monitor the value of Average Wait Time Per Reques, and you should consider adding Shared Servers when this value continues to grow.
Select Decode (Totalq, 0, 'No Requests') "Wait Time",
Wait / Totalq || 'Hundredths of Seconds' "Average Wait Time Per Request"
From v $ queue
WHERE TYPE = 'Common'
4, how do you connect the SERVER request Dedicate in the MTS configuration?
When you do a service name in tnsnames.ora, you can add SRVR = dedicated this option, as follows:
Billing =
(Description =
(
Address_List = (Address = (Protocol = TCP) (Host = KS3) (port = 1521))
)
(
Connect_data =
(Service_name = billing)
(SRVR = DEDICATED)
)
)
Sixth, the end
Using MTS is a nice choice when your Oracle's server has high memory utilization and frequent page. Overall, MTS is more suitable for the type of OLTP, for those data warehouses, DDS these types of applications are not suitable.
