Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
![]() |
![]() |
Home -> Community -> Mailing Lists -> Oracle-L -> Re: sequential read on full-table scan?
Zoran,
I took your advice and found some interesting information. Here's a typical snippet of the trace file:
WAIT #64: nam=3D'db file scattered read' ela=3D 1150 p1=3D17 p2=3D9813 p3=
=3D3
WAIT #64: nam=3D'db file scattered read' ela=3D 959 p1=3D17 p2=3D9817 p3=3D=
2
WAIT #64: nam=3D'db file sequential read' ela=3D 2040 p1=3D17 p2=3D9820 p3=
=3D1
WAIT #64: nam=3D'db file sequential read' ela=3D 547 p1=3D17 p2=3D9822 p3=
=3D1
Note that there ARE scattered reads going on as well as sequential, but the scattered reads are grabbing only 2 or 3 blocks at a time. DB file multiblock read count is set to 16.
Paul
On 5/20/05, Martic Zoran <zoran_martic_at_yahoo.com> wrote:
> Paul,
> Wanted to say fact 3 (buffer in the cache) + sometimes > fact 2 (extent edge).
> Zoran
> __________________________________ > Do you Yahoo!? > Make Yahoo! your home page
--=20
Paul Baumgartel
paul.baumgartel_at_gmail.com
-- http://www.freelists.org/webpage/oracle-lReceived on Fri May 20 2005 - 17:38:54 CDT
![]() |
![]() |