Chapter 4: Configuration > 4.2 Configuration Variables > 4.2.2 Server Configuration Variables >

V_INDEX_BLOCK_PERCENT

Because the index data stored in index segments is often much smaller than the record data contained in data segments of Vision 5 files, a large pre-allocate or extension factor typically allocates many more blocks than are needed. V_INDEX_BLOCK_PERCENT allows you to determine the ratio of index block to data blocks that are created for a Vision file, which can help trim file size when disk space is tight.

When V_INDEX_BLOCK_PERCENT is set to a value smaller than 100, fewer index blocks are created than data blocks. When this variable is set to a value greater than 100, more index blocks are created than data blocks. The value range for V_INDEX_BLOCK_PERCENT is 1 to 1000, and the default value is 100.

For example, if you have a file with an extension factor of 10 and set V_INDEX_BLOCK_PERCENT to 50, the next time the file is extended, 10 new data blocks and 5 new index blocks are created. If you set V_INDEX_BLOCK_PERCENT to 200 for the same file, the next time the file is extended, 10 new data blocks and 20 new index blocks are created.