DB2 Server for VSE & VM: Performance Tuning Handbook

Using Data Spaces with Internal Dbspaces

This section describes how to use internal dbspaces with data spaces. For information on whether these dbspaces should be mapped or unmapped, refer to Internal Dbspaces.

Unmapped Internal Dbspaces

To use separate (unmapped) internal dbspaces, set the initialization parameter SEPINTDB to "Y" (Y is the default). For example:

+--------------------------------------------------------------------------------+
|sqlstart db(SQLDBA) parm(sepintdb=Y)                                            |
|ARI0717I Start SQLSTART EXEC: 05/23/99 09:44:24 EDT.                            |
|ARI0320I The default database name is SQLDBA.                                   |
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|ARI0015I SEPINTDB parameter value is Y.                                         |
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+--------------------------------------------------------------------------------+

Message ARI0015I should tell you that the SEPINTDB parameter is set to Y. If it does not, check that you are operating your database machine in XC mode. You cannot use unmapped internal dbspaces in ESA mode.

Before you use unmapped internal dbspaces, you must allocate more DASD to VM system paging. Refer to VM/ESA Paging DASD.

Attention: If VM runs out of system paging DASD, CP will abend if it does not have sufficient spool DASD to accommodate the overflow.

Mapped Internal Dbspaces

To use mapped internal dbspaces, turn Data Spaces Support on for the storage pool containing internal dbspaces and set the initialization parameter SEPINTDB to "N". For example:

+--------------------------------------------------------------------------------+
|sqlstart db(SQLDBA) parm(sepintdb=N)                                            |
|ARI0717I Start SQLSTART EXEC: 05/23/99 09:39:02 EDT.                            |
|ARI0320I The default database name is SQLDBA.                                   |
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|ARI0015I SEPINTDB parameter value is N.                                         |
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+--------------------------------------------------------------------------------+

Note, just setting SEPINTDB=N does not turn Data Spaces Support on or off for your internal dbspaces. You can use either Data Spaces Support or the standard DASD I/O system with internal dbspaces. Because internal dbspaces are assigned to one storage pool, they will use whichever DASD I/O system is specified for that pool (see Specifying Either Data Spaces Support or Standard DASD I/O).

Note:

A storage pool used only for internal dbspaces and which as a dbextent on a virtual disk cannot be used with data spaces turned on for that pool. This storage pool must be specified with the BLK and SEQ options in the storage pool specification file. See Appendix A, Storage Pool Specification File Format.