HPL and index creation times

Hi, I=92ve been doing some test loads using the HPL into a fragmented and an = unfragmented table. Basically, the test platform is as follows: HP K410 = dual cpu machine, 256Mbyte memory, with the database built on 4 (mirrored= ) EMC disks. Two tables are loaded. They have the same columns and each have the same = 3 indexes. One table is unfragmented, the other has 3 fragments. Each fra= gment is on a different disk, with the indexes detached, residing on the = fourth disk. Round Robin fragmentation is used. The tables are loaded wit= h the same 1.4 million rows from a single source file. The test loads are run at night when the machine has no other work on it,= the tables are dropped and recreated (including the indexes) just prior = to loading. The tables are sized to get all the data in the first extent.= In the unfragmented table, the first extent includes the indexes. I=92ve= tried varying each of the parameters in the plconfig file over a range = of values. The only one that seems to make a difference is CONVERTTHREADS= . If this is set to 1 then the load times are: Fragmented table: 504 seconds to load, 624 seconds to build the indexes Unfragmented table: 507 second to load, 234 seconds to build the indexes If CONVERTTHREADS is set to 2 or more then the load times are: Fragmented table: 265 seconds to load, 613 seconds to build the indexes Unfragmented table: 267 second to load, 239 seconds to build the indexes The other variables in plconfig can be varied from the default, but there= is no significant difference in the times. Now we come to my question: = why does the fragmented table take 2.5 times longer to build its indexes = compared with the unfragmented equivalent? I notice from using oncheck -pt that the detached indexes each have their= own space allocated. Does this mean that detached indexes are built one = at a time, each requiring a scan of the data? If this is so, does the unf= ragmented table build its indexes via a single pass of the data, collecti= ng all the key values as it goes? -I=92m guessing here. Whatever the answ= er, I seem to be paying a very heavy cost for using detached indexes. Thanks for any responses, as the HPL seems to be largely ignored by this = news group. Martyn Hodgson martyn.hodgson@eaglestar.co.uk