What are the execution plans for each? I would recommend a DOP that is a power of 2 (2/4/8/16/...), as it leads to the most even distribution of work (similar to why power of 2 is recommended for the number of hash partitions - it yields the best/even distribution of keys). On Wed, Mar 11, 2009 at 2:18 PM, Keith Moore <kmoore@xxxxxxxxxxxx> wrote: > Oracle 9.2.0.4 > Solaris 8 > > I have a database where creating an index on a particular table takes about 25 > minutes but if I create a similar index on the same table with the "PARALLEL > 3" clause it takes over 100 minutes. > > I ran a 10046 trace on both statements and the normal CREATE INDEX does > multiblock (scattered) reads, generally 1 Megabyte per read. The problem is > that the index created PARALLEL 3 does single block (sequential) reads. > > Can anyone explain why it would do single block reads? Is this a bug? -- Regards, Greg Rahn http://structureddata.org -- //www.freelists.org/webpage/oracle-l