Hi Guys,

Can any one please help me understand why on earth Oracle decides the extent size by its choice in case of Parallel DML?

below is a test case and am bit confused..

Code:
DBA> select segment_name, segment_type, .. from dba_segments where segment_name = upper('Temp_Open_Order_Detail');

SEGMENT_NAME               SEGMENT_TYPE       TABLESPACE_NAME              BYTES       BLOCKS    EXTENTS       INITIAL_EXTENT   NEXT_EXTENT    PCT_INCREASE
-------------------------- ------------------ ----------------- ---------------- ------------ ---------- -------------------- -------------  --------------
TEMP_OPEN_ORDER_DETAIL     TABLE              WWCIW_TAB_2              287309824        35072          5            209715200     209715200               0

DBA> select segment_name, segment_type, .. from dba_extents where segment_name = upper('temp_Open_Order_Detail') order by EXTENT_ID;

SEGMENT_NAME                 SEGMENT_TYPE       TABLESPACE_NAME     EXTENT_ID         BYTES   BLOCKS 
---------------------------- ------------------ ----------------- -----------  ------------ -------- 
TEMP_OPEN_ORDER_DETAIL       TABLE              WWCIW_TAB_2                 0     209715200    25600 
TEMP_OPEN_ORDER_DETAIL       TABLE              WWCIW_TAB_2                 1      37216256     4543 
TEMP_OPEN_ORDER_DETAIL       TABLE              WWCIW_TAB_2                 2      37232640     4545 
TEMP_OPEN_ORDER_DETAIL       TABLE              WWCIW_TAB_2                 3       1581056      193 
TEMP_OPEN_ORDER_DETAIL       TABLE              WWCIW_TAB_2                 4       1564672      191 

DBA> select TABLESPACE_NAME, EXTENT_MANAGEMENT, ALLOCATION_TYPE, SEGMENT_SPACE_MANAGEMENT from
  2  dba_tablespaces where TABLESPACE_NAME = 'WWCIW_TAB_2';

TABLESPACE_NAME                EXTENT_MAN ALLOCATIO SEGMEN
------------------------------ ---------- --------- ------
WWCIW_TAB_2                    DICTIONARY USER      MANUAL
If you see above initial and next are 200M and also pct increase is 0.

now why is oracle allocating those happazard sized extents??

Well if i insert into this table serially then extents are of 200M but if i say "Alter Session Force Parallel DML" then am seeing these happazard extents..

Abhay.