13.1.5 Additional installation steps

13.1.5.1 Firewall Settings

For the normal operation of PVSR, the following connections need to be enabled on the firewall between the system components:

13.1.5.2 Database sizing

As the first step of the installation the database schema needs to be created in the Oracle database. The define.sql file contains the necessary parameters, which can be divided into two parts: tablespace configuration and table and partition size configuration.

Tablespace

The application can optionally use two separate tablespaces: one for the configuration tables (pvsr_conf_data_tablespace) and one for the measurement data (pvsr_res_data_tablespace). The measurement data is stored in so called IOTs, i.e. in Index Organized Tables, which means that there is no separate index and data storage; therefore there is no index tablespace either.

Two configuration options are supported for tablespaces (for more detail, see Oracle 9i Database Concepts):

• locally managed with uniform extent sizing
• dictionary managed with the same INITIAL and NEXT values

In both cases the data storage units of the database – the so called extents – will be of the same size. This is important for the application in order to put the smallest load on the database when the optionally freed storage, after the deletion of measurement data, is reallocated.

The above mentioned uniform extent size fundamentally determines the size of the tables and partitions. Based on the tablespace and the use of the optional partitioning, we recommend the following:

• the tablespace containing the configuration: the amount of data stored here is insignificant compared to the size of tables storing the measurement data, therefore low values (such as 32-64K) can be used
• tablespace storing the measurement data:
• when partitioning is used: in order to create the smallest number of new extents, choose the greatest common divisor of the planned partition sizes. Warning: the data of only a single partition is stored in an extent, therefore unrealistic large extent sizes will result in wasted space that the application will not be able to use. After the initial installation it is possible to specify on a table-by-table basis that the application should create further partitions in another tablespace. If we do not wish to use one of the options (such as threshold alarms), then it is recommended to create those in a separate tablespace with small size. Typical values: 128-512K
• when partitioning is not used: in this case we can safely specify large values as well, since no multiple-use regions are created. Typical value: 1M-10M

Table or partition sizes

The meaning of the following parameters depends on whether the application is used with partitions or normal tables:

• For normal tables: The parameters specify the initial sizes of the table
• For partitioned tables: The parameters specify the default size of newly created partitions. The PVSR_RES_PART table is filled up during installation with these parameters, and new partitions are created subsequently based on the data stored in this table. If we wish to modify the values specified in the define.sql file after the installation, then the values of the MINEXTENTS_NUMBER and TBS_NAME parameters need to be changed in the row corresponding to the table whose name is stored in the TABLE_NAME column.

Since in the partitioned case new partitions are created at certain time intervals, therefore the sizing should be chosen accordingly, striving not only for the creation of minimally fragmented tables, but also for minimizing the size of the wasted partition regions. The time intervals in the following table and in the define.sql file are specified in hours. For each table there is a parameter named …_minext, which controls the number of extents reserved initially.