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

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Sybase IQ 12.4.0 installation instructions Adaptive Server IQ Description, Insertnumberrowsperrawiobuffer