If this is UFS, you should be able to tunefs to set fs_maxcontig to limit the size of the gobbling an FS read-ahead reads in. The wont control just how far a read-ahead reaches though. What you need (and I don't know how to track this on HPUX) is visibility into the read-ahead blocks visited. All Fses I've worked on track that. It is important to know whether or not RA is getting triggered for stuff that never gets visited. >>>-----Original Message----- >>>From: Kevin Lidh [mailto:kevin.lidh@xxxxxxxxx] >>>Sent: Tuesday, December 19, 2006 1:22 PM >>>To: kevinc@xxxxxxxxxxxxx >>>Cc: oracle-l@xxxxxxxxxxxxx >>>Subject: RE: db_file_multiblock_read_count causing full >>>scans to takelonger? >>> >>>In my case, it's filesystem. Is there a parameter that >>>determines read-aheads? I'll look for HP-UX but if you know > -- http://www.freelists.org/webpage/oracle-l