User exit for logging status                            = NO

In Example 9 28 

Multi page

 was not enabled. This can be changed by running 

the 

db2empfa

 program on the target database. Since 

db2empfa

 connects to the 

database in exclusive mode, all other users should be disconnected from the 

database. After 

db2empfa

 execution against the target database, check the 

multi page file allocation parameter for the status (see Example 9 29).

Example 9 29   Enabling multi page allocation

$db2empfa sample

$db2 get db cfg for sample

Rollforward pending                                     = NO

Restore pending                                         = NO

Multi page file allocation enabled                      = YES

Log retain for recovery status                          = NO

User exit for logging status                            = NO

Better insert performance can be achieved with 

Database Managed Spaces 

(DMS)

 because containers are pre allocated and management of the I/O 

operations is shifted to the database engine. In DB2 UDB Version 8 you can 

easily add new containers, drop, or modify the size of existing containers. Data is 

rebalanced to other containers automatically unless instructed. The 

administrative overhead is not so significant when compared to the SMS table 

spaces. 

For optimal performance, large volume data and indexes should be placed on 

DMS table spaces; if possible, split to separate raw devices. Initially, system 

catalogs and system temporary table spaces should stay on the SMS table 

spaces. System catalogs contain large objects, which are not cached by the DB2 

UDB engine, and can be cached by the operating system cache. In an OLTP 

environment, there is no need for creating large temporary objects to process 

SQL queries, so the SMS system temporary table space is a good starting point. 

9.5.2  Physical placement of database objects

When creating a database, the first important decision is the storage 

architecture. The ideal situation is to have the fastest disks as possible and at 

least five to ten disks per processor (for high I/O OLTP workload use even more). 

The reality is the hardware is often chosen based on other considerations, so in 

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MySQL to DB2 UDB Conversion Guide