Oracle8
and above rounds off extents to multiple of 5 blocks when more than 5 blocks
are requested
If
one requests 16K or 2 blocks (assuming an 8K block size), Oracle doesn't round
it up to 5 blocks, but it allocates 2 blocks or 16K as requested.
If one asks
for 8 blocks, Oracle will round it up to 10 blocks.
Space allocation also depends upon size of contiguous free space available. If one asks for 8 blocks and Oracle finds contiguous free space that are exactly 8 blocks it would give it to you.
Space allocation also depends upon size of contiguous free space available. If one asks for 8 blocks and Oracle finds contiguous free space that are exactly 8 blocks it would give it to you.
If
it were 9 blocks, Oracle would also give it to you.
Clearly Oracle doesn't
always round extents to a multiple of 5 blocks.
The exception to this rule is locally managed table spaces. If a table space is created with local extent management and the extent size is 64K, then Oracle allocates 64K or 8 blocks assuming 8K – block size. Oracle doesn't round it up to multiple of 5 when a tablespace is locally managed
The exception to this rule is locally managed table spaces. If a table space is created with local extent management and the extent size is 64K, then Oracle allocates 64K or 8 blocks assuming 8K – block size. Oracle doesn't round it up to multiple of 5 when a tablespace is locally managed