Sybase 12.4.2 manual Setting buffer cache size database options, 428

Overview of memory use

		How long the setting is	For more
Method	When to use it	effective	information, see
-iqmc and -iqtc server	Reset cache sizes when	From the time the server is	“Setting buffer cache
switches	the database is not	started until it is stopped	size server switches” on
	running. Especially useful		page 429
	if cache sizes are larger
	than your system can
	accommodate.
-iqsmem and -iqwmem	Use on some UNIX	From the time the server is	“Platform-specific
server switches	platforms to provide	started until it is stopped	memory options” on
	additional memory for use		page 434
	as buffer caches.
LOAD_MEMORY_MB	Indirectly affects buffer	Immediately until you reset	“Memory for loads,
database option	cache size, by controlling	the option	synchronizations, and
	the memory that can be		deletions” on page 421
	used for loads. On some
	platforms, allowing
	unlimited memory for
	loads means less memory
	is available for buffer
	caches.

Setting buffer cache size database options

To set buffer cache sizes permanently (that is, until you explicitly reset them) use the SET OPTION statement. Follow the procedure below.

❖To change the buffer cache sizes permanently:

1If the database whose cache sizes you are changing is not already started, start it now:

START DATABASE dbfile [AS dbname] [ON engine_name]

2 Set one or both cache sizes.

•To set the buffer cache size for the IQ Store (the main buffer cache) use the following syntax:

SET OPTION "PUBLIC".MAIN_CACHE_MEMORY_MB =

#_of_MB

•To set the buffer cache size for the Temporary Store (the temp buffer cache) use the following syntax:

SET OPTION "PUBLIC".TEMP_CACHE_MEMORY_MB =

#_of_MB

428