Setting Db2 for z/OS subsystem parameters for Data Gate on Cloud
You can set the Db2 for z/OS subsystem
parameters that are required for Data Gate on Cloud on
the DSNTIP82
installation panel in Db2 for z/OS or customize and run the
DSNTIJUZ
sample job.
About this task
You must set the following Db2 subsystem parameters:
- ACCEL
- Set this subsystem parameter to the value
AUTO
(ACCEL=AUTO)
. This means that Data Gate on Cloud is started automatically by Db2 for z/OS. - AUTH_COMPATIBILITY
- Set this subsystem parameter to
SELECT_FOR_UNLOAD
to ensure proper privileges for the initial load of data into Data Gate on Cloud. - CMTSTAT
- Set this to
CMTSTAT=INACTIVE
, which is also the default. So you have to change the parameter value just in case the current value isACTIVE
. You need not change the setting if the parameter is not set at all.The CMTSTAT subsystem parameter controls whether in-use database access threads (DBATS) can be pooled, for use by other connections, after they successfully commit or roll back. For more information, see DDF THREADS field (CMTSTAT subsystem parameter).
The setting
CMTSTAT=ACTIVE
is rarely used these days and has not been recommended for a long time. In the past, a performance improvement could be achieved by using it in a controlled environment with a fixed (known) number of connections.However, the use of this setting leads to a drawback if the number of connections varies. To restrict or control the number of connections, you need to set the
MAXDBAT
parameter, which defines a maximum for the number of connections. For example, if you want 10000 client connections, you have to setMAXDBAT
to 10000. The use of such a limit is very resource-intensive.Another drawback is that HTTP sessions cannot be reused. This means that every single HTTP request requires an SSL handshake. This is true for both, the HTTP application programming interface (API) and the log reader API of Db2 for z/OS. The higher demand for SSL handshakes binds AT-TLS resources unnecessarily.
- TCPKPALV
- Set this parameter to the integer value
120
orENABLE
. The value120
is also the default. The valueENABLE
means that the TCP/IPKeepAlive
configuration value is used and not overridden with theTCPKPALV
value instead (see the TCPCONFIG code sample). Change the parameter value just in case it is set toDISABLE
. You need not change the setting if the parameter is not set at all.The TCPKPALV subsystem parameter determines whether the TCP/IP KeepAlive value in the TCP/IP configuration is to be overridden with a different value. For more information, see TCP/IP KEEPALIVE field (TCPKPALV subsystem parameter)
- POOLINAC
- Set this parameter to the integer value
120
, which is also the default. So you have to change this parameter just in case it is set to a different value. You need not change the setting if the parameter is not set at all.The POOLINAC subsystem parameter specifies the approximate time, in seconds, that a database access thread (DBAT) can remain idle in the pool before it is terminated. For more information, see POOL THREAD TIMEOUT field (POOLINAC subsystem parameter)