IBM 000-8697 Manual Do Utilizador
System Architecture
2-119
Next Extent Allocation
Figure 2-24
When one extent
fills, another is
automatically
allocated. Because
OnLine considers
several factors
during allocation,
the size of the next
extent may not
always be the size
specified in the
CREATE TABLE
statement.
Chunk 1
Chunk 1
3rd extent
Next extent allocation
3rd extent
Chunk 1
3rd extent
Chunk 6
64th extent
65th extent size is doubled
Next Extent Allocation Strategies
Extent sizes double every 64 extents.
If the dbspace is too full to accommodate the next extent size, OnLine allocates the
largest available contiguous block of disk space.
largest available contiguous block of disk space.
4th extent
If the next extent is physically contiguous with an existing extent for the same
tblspace, the disk space is treated as a single extent.
tblspace, the disk space is treated as a single extent.
Some other tblspace extent