Sybase IQ 12.4.0 Adaptive Server IQ Description, Insertnumberrowsperrawiobuffer

Adaptive Server IQ 12.4.0		Description
Description	This option specifies an upper bound (in MB) on the amount of heap memory
	subsequent loads can use. The default setting, 0 (zero), means that there is no
	upper bound, and Adaptive Server IQ can use as much heap memory as
	necessary to perform the load. A non-zero value means that the user has set an
	upper bound. This option is typically used for LOAD statements, but affects all
	operations where loads occur, including SYNCHRONIZE and DELETE
	operations.
	Setting a non-zero value for this option is typically done to avoid
	overallocating the physical memory on the machine and exhausting virtual
	memory during a load operation. Given a user-specified upper limit, the load
	process will attempt to ensure that the load can succeed even if it means
	incurring degradation in load performance. However, every load requires some
	minimal amount of heap memory. If the user-specified limit is lower than this
	amount, the user will receive the following error:
	The load user approximately <x> MB, but only <y> MB was specified
	where <x> is a rough approximation of the minimum amount of heap memory
	needed and <y> is the upper limit set by the user. If this error occurs, then the
	user must increase or turn off the Load_Memory_MB option and try again.
	We are removing the following options and replacing them with the new
	LOAD_MEMORY_MB option:
	•	INSERT_NUMBER_PRODUCERS
	•	INSERT_NUMBER_MT_BUFFERS
	•	INSERT_NUMBER_RAW_IO_BUFFERS
	•	INSERT_NUMBER_ROWS_PER_BUFFER
	•	INSERT_NUMBER_ROWS_PER_RAW_IO_BUFFER

JOIN_PREFERENCE Option

Function

Allowed Values

Default

This version includes two new option values, 6 and –6 to prefer or avoid using a join index.

Controls the choice of algorithms when processing joins.

-6 to 6

0

Release Bulletin for Digital UNIX 31