10.1.1 System design

Organization of this subsection
(1) Server configuration
(2) Placement of system manager
(3) Placement of floating server
(4) Using multiple front-end servers
(5) Storage requirements

(1) Server configuration

The basic configuration of a HiRDB/Parallel Server consists of a front-end server, dictionary server, and back-end server on the same server machine.

If the CPU workload of the server machine is low, multiple servers may be placed on one server machine. In such a case, more shared memory is required. If there is not enough shared memory, unit startup fails; for this reason, sufficient memory must be allocated.

Table 10-1 shows the permitted number of servers you can install.

Table 10-1 Number of permitted servers

ItemNumber of permitted servers
Number of system managers1
Number of front-end servers1 to 1,024
Number of dictionary servers1
Number of back-end servers1 to 16,382
Number of servers per unit1 to 34

(2) Placement of system manager

The server machine on which the system manager is defined should be at a location that is easily accessible by the HiRDB administrator for the following reasons:

(3) Placement of floating server

When a complicated retrieval such as join processing is executed, it is better for HiRDB to use a back-end server that does not have a database in order to improve performance. If the server machine has sufficient space and complicated retrieval processing is to be performed, installation of a floating server should be considered. When a floating server is installed, a HiRDB file system area for work table files must be created. The name of this HiRDB file system area is specified in the pdwork operand of the back-end server definition.

(4) Using multiple front-end servers

If the CPU workload for SQL processing is too high to be processed on the front-end server, multiple front-end servers can be set up. This is called multiple front-end servers; for details, see 10.1.3 Setting up multiple front-end servers.

(5) Storage requirements

The storage space required by the HiRDB/Parallel Server must be estimated for each server machine. For details about how to estimate the storage requirements, see 16.2 Estimating the memory size required for a HiRDB/Parallel Server.