Syntax options:

    EXTENT ENABLED | EXTENT DISABLED

    Enables or disables extents. Extents are ENABLED by default.

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