Expanded Processor Control: CPU AFFINITY

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On Windows multiprocessor platforms, you can specify which processors InterBase should use by adding the CPU_AFFINITY parameter to the ibconfig file. This setting is useful whenever the number of licensed processors is less than the number of actual processors present.

Important: Note that when you purchase a single server license, you acquire the right to use a single processor. You must purchase one additional license for each additional processor that you wish to use.

The CPU_AFFINITY parameter populates a bit vector in which each bit represents a processor on the system on which the threads are allowed to run. The maximum number of processors depends on the operating system. To specify which processors should be used, give CPU_AFFINITY a decimal value that corresponds to the binary value that results from setting a bit for each desired machine. For example, to use processors 2 and 3, set CPU_AFFINITY to 6:

CPU_AFFINITY 6

To use these processors	CPU_AFFINITY value	Array setting
1	1	0 0 1
2	2	0 1 0
1 and 2	3	0 1 1
3	4	1 0 0
2 and 3	6	1 1 0
1, 2, and 3	7	1 1 1