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DB2 database server in three-tiered configuration
To use the DB2 database server in a three-tiered configuration, the following settings are
required:
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Separate log files and containers onto separate (RAID) disks
Increase log file size for twproc database to 16384 pages)
Enable file system caching for twproc database:
db2 alter tablespace userspace1 file system caching
Exclude the table SIBOWNER from automatic runstats execution, as described in the
following technote:
http://www.ibm.com/support/docview.wss?uid=swg21452323
Ensure that database statistics are current.
If running at high throughput rates, consider disabling some or all database
auto-maintenance tasks to avoid impacting peak throughput. However, if you disable these
capabilities, be sure to use runstats regularly to update database statistics
Use your database vendor’s tool to obtain recommendations for indexes to create; this
task is necessary because different applications often require unique indexes. Create the
indexes that are suggested by the database vendor’s tool.
5.1.3 Two-tiered: Using file store for Java Message Service
We used a two-tiered configuration to evaluate the performance of a long-running business
process that models a typical mortgage application process. This configuration is used with
the Business Process Manager server and DB2 on the same physical system as is common
for proofs-of-concept when limited hardware is available. However, the configuration is not a
representative production configuration. Java Message Service (JMS) binding is used for
communication.
In this configuration, the BPE uses a DB2 database, and the messaging engines are
configured to use file stores. To select the file store option, start the Profile Management Tool,
click Advanced Profile Creation, and in the Database Configuration window, click Use a file
store for Messaging Engines.
Tuning parameter settings for the BPE database were initially derived using the DB2
Configuration Advisor. The following key parameter settings are modified further:
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MAXAPPLS is enlarged enough to accommodate connections from all possible JDBC
Connection Pool threads.
The default buffer pool sizes (number of 4 KB pages in IBMDEFAULTBP) for each
database are set so that each pool is 256 MB in size.
102 IBM Business Process Manager V8.0 Performance Tuning and Best Practices