V_INDEX_BLOCK_PERCENT

This configuration variable allows you to specify index pre-allocate and extension factors as a percentage of the factors applied to the data segment. In Vision 4 and 5 files, the index data contained in the index segments is often much smaller than the record data contained in the data segments. As a result, a large pre-allocate or extension factor typically allocates many more index blocks than are needed. This can be undesirable, especially if disk space is tight.

Setting V_INDEX_BLOCK_PERCENT to a number less than 100 causes fewer index blocks than data blocks to be created. Setting the variable to a number greater than 100 causes more index blocks than data blocks to be created. The valid range for V_INDEX_BLOCK_PERCENT is one through 1000. If the value specified is less than one, it will be promoted to one. V_INDEX_BLOCK_PERCENT is set to 100 by default (the default pre-allocate and extension factors for a file).

For example, if a file has an extension factor of 10, setting V_INDEX_BLOCK_PERCENT to 50 causes 10 new data blocks and five new index blocks to be created the next time the file is extended. Setting V_INDEX_BLOCK_PERCENT to 200 causes 10 new data blocks and 20 new index blocks to be created the next time the file is extended.

Note: The number of blocks pre-allocated will never be larger than that which can fit in the initial data and index segments. If the pre-allocation value specified or calculated from V_INDEX_BLOCK_PERCENT is larger than the segment size, the pre-allocation amount is automatically reduced to the segment size.