Sybase 12.4.2 manual Setting switches that affect timing

-iqsmem

CHAPTER 2 Running Adaptive Server IQ

Unwired memory

Number of processing threads

Catalog Store cache size

The -iqsmemswitch creates a memory pool to increase total available memory. This switch is available on all UNIX platforms, but is required in some cases:

•On HP systems use -iqsmemif you want to use more than 2GB of memory. The value should be between 500 and 1400MB.

•On AIX systems always use -iqsmem. The value for -iqsmemshould be between 356 and 2560; otherwise, the server aborts.

Specify this switch as the number of megabytes of memory. The maximum

value for is 2000. For example, to add 1GB of unwired memory you specify:

-iqsmem 1000

Use the -iqmtswitch to set the number of processing threads that Adaptive Server IQ can use. Adaptive Server IQ assigns varying numbers of kernel threads to each user connection, based on the type of processing being done by that process, the total number of threads available, and the setting of various options. Increasing the number of threads can improve performance.

Use the -cswitch to set the amount of memory in the cache for the Catalog Store. The default initial cache size is computed based on the amount of physical memory, the operating system, and the size of the database files. On Windows NT, the database server takes additional cache for the Catalog when the available cache is exhausted.

For many Adaptive Server IQ and Java applications, you need to raise the size of the Catalog cache above the default value of 2MB. Any cache size less than 10000 is assumed to be in KB (1K =1024 bytes); any cache size 10000 or greater is assumed to be in bytes. You can also specify the cache size as nK or nM.

Both start_asiq and the asiqdemo.cfg configuration file set this parameter to 16MB.

Note The cache size for the IQ Store does not rely on the Catalog cache size. See “IQ buffer cache sizes.”

Setting switches that affect timing

Checkpoint interval Adaptive Server IQ uses checkpoints to generate reference points and other information that it needs to recover databases. Use the -gcswitch to set the maximum desired length of time (in minutes) that the database server will run without doing a checkpoint. The default value is 60 minutes.

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