Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> RE: db_file_multiblock_read_count causing full scans to takelonger?

RE: db_file_multiblock_read_count causing full scans to takelonger?

From: Kevin Closson <kevinc_at_polyserve.com>
Date: Tue, 19 Dec 2006 13:03:07 -0800
Message-ID: <5D2570CAFC98974F9B6A759D1C74BAD001C3382A@ex2.ms.polyserve.com>

 

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_at_freelists.org
>>>[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Kevin Lidh
>>>Sent: Tuesday, December 19, 2006 12:58 PM
>>>To: Allen, Brandon
>>>Cc: oracle-l_at_freelists.org
>>>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
>

--
http://www.freelists.org/webpage/oracle-l
Received on Tue Dec 19 2006 - 15:03:07 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US