Is this direct I/O or a filesystem? Could the filesystem be firing off some uneccessary read-aheads when you do large dfmbrc but not when you are nibbling with smaller multiblock request? >>>-----Original Message----- >>>From: oracle-l-bounce@xxxxxxxxxxxxx >>>[mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Kevin Lidh >>>Sent: Tuesday, December 19, 2006 12:58 PM >>>To: Allen, Brandon >>>Cc: oracle-l@xxxxxxxxxxxxx >>>Subject: RE: db_file_multiblock_read_count causing full >>>scans to takelonger? >>> >>>Well, that's what contributed to my confusion. In my trace >>>files, which are 9i so slightly different: >>> >>>WAIT #1: nam='db file scattered read' ela= 21614 p1=6 p2=3979 p3=126 >>>--> 126 blocks = 21614 > -- //www.freelists.org/webpage/oracle-l