Tuning DB2 and LDAP caches
You can tune the DB2® database that is configured with a directory server instance to reduce the search and update time.
IBM® Security Directory Server uses DB2 as the data store; and Structured Query Language (SQL) as the query retrieval mechanism. While the LDAP server caches LDAP queries, results, and authentication information; DB2 caches tables, indexes, and statements.
Many DB2 configuration
parameters affect either the memory (buffer pools) or disk resources.
Since disk access is usually much slower than memory access, the key
database performance tuning objective is to decrease the amount of
disk activity. In DB2, Version 11.5.7.0, you
can use Self Tuning Memory Manager (STMM) instead of manually tuning
several DB2 parameters.
When you use the STMM, DB2 assigns
the correct values to memory consumers based on the usage of the system
and available resources. You can use the DB2 STMM by
setting the values of DB2 buffer
pool to AUTOMATIC
.
When you tune DB2, you must consider the following options:
- Tuning DB2 buffer pool
- Tuning DB2 and LDAP caches by using the idsperftune tool
- Database maintenance by using the idsdbmaint tool. You can use the tool for DB2 index organization, DB2 row compression, and table space conversion.
- Database maintenance by using the idsrunstats tool.
- Optimization and organization (reorgchk and reorg)
- Other DB2 configuration parameters
- Backup and restore the database
- Data row compression
For more information about DB2 commands, see the DB2 documentation at http://www-01.ibm.com/support/knowledgecenter/SSEPGG/welcome.
db2
commands, you must user a user
ID that in a member of the dbsysadm
group (UNIX operating systems) or a member
of the Administrator group (Windows operating
systems.) The DB2 instance
owner and root are members of the dbsysadm
group. If you have any issues when you run the DB2 commands,
check to ensure that the DB2 environment
variables are set by running db2profile. If not,
the db2 get and db2 update commands
might not work. The script file db2profile is
in the sqllib subdirectory of the instance owner
home directory. To modify the file, follow the comments inside the
file to set your instance name, user paths, and default database name
(the default path is /home/ldapdb2/sqllib/db2profile.)
It is assumed that the user is logged in as ibm-slapdDbUserId
.
If logged in as the root user on a UNIX operating
system, you can switch the user context to the instance owner.
su - instance_owner
where, instance_owner is the defined owner of the LDAP database.
To log on as the database administrator on a Windows 2000 operating system, run the following command:
runas /user:instance_owner db2cmd
where, instance_owner is the defined owner of the LDAP database.