Syntax options:

    EXTENT IS ENABLED | EXTENT IS DISABLED

    Enables or disables extents. Extents are enabled by default.

    You can encounter performance problems when creating hashed
    indexes in storage areas with the mixed page format if the
    storage area was created specifying the wrong size for the area
    and if extents are enabled. By disabling extents, this problem
    can be diagnosed early and corrected to improve performance.