Kbase P23054: What is the amount of shared memory represented by each unit of the database startup parameter (-B )
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
07/02/2009 |
|
Status: Verified
GOAL:
What is the amount of shared memory represented by each unit of the database buffer startup parameter (-B )?
FIX:
The value of each unit depends on the block size of the database, i.e. a database with an 8K (8192 bytes) block size plus 150 bytes for the buffer header would give a value of 8342 bytes for each database buffer (-B).
The header value is the same for all database block sizes.
The default value for -B (database buffers)is 8* number of "user" processes as noted by the startup parameter -n, i.e. [8 * default -n value(21) is 168].
The default value is a -B of 168.
In this example, multiply 168 * 8342 bytes=1401456 bytes = about 1.33MB of shared memory for a database with default settings.