Hi Are you try this: alter system set FAST_START_PARALLEL_ROLLBACK=false. I encountered this problem also and FAST_START_PARALLEL_ROLLBACK=false helped me. Best regards, Pavel Ermakov. 2010/7/24 dd yakkali <dd.yakkali@xxxxxxxxx> > I was able to do this by killing the OS server process for that session and > then SMON picked it up and rolled it back with parallel 32. > > thanks > Deen > > On Thu, Jul 22, 2010 at 6:13 PM, dd yakkali <dd.yakkali@xxxxxxxxx> wrote: > >> we killed a merge sql which was running in serial and the rollback is >> taking a long time. We are on 10.2.0.4, is there any way to speed up the >> rollback process. >> >> we have FAST_START_PARALLEL_ROLLBACK set to LOW. >> >> We are on a RAC system. >> >> any help is greatly appreciated. >> Thanks >> Deen >> > >