If the application frequently performs UPDATES that alter sizes of rows
greatly, then PCTFREE can be set high and PCTUSED can be set low. This would
allow for large amount of space in data blocks for row size growth.
If there is more INSERT activity with less UPDATES, the PCTFREE can be set
low with average value for PCTUSED to avoid chaining of rows.
If the main concern is performance and more space is available, then
PCTFREE can be set very high and PCTUSED very low.
If the main concern in space and not performance, then PCTFREE can set very
low and PCTUSED very high.
The default values of PCTFREE is 10 and PCTUSED is 40.
