??? We would need a lot more info. What platform? what Release? Memory? Table declaration? Indexes? DB config? DBM Config? How are you inserting? Are you inserting from a select statement? from a flat file? Why are you inserting(vs. loading)? Is HADR involved? Q/REP? Are there any triggers? Disk i/o issues? What type of data?
Your question is kind of like asking a blind person to describe the color green.