Inconsistent multi-block io

From: <maks71_at_gmail.com>
Date: Mon, 7 Jul 2008 14:19:00 -0700 (PDT)
Message-ID: <3806359c-4be0-4284-a803-2f5796b5fc53@a1g2000hsb.googlegroups.com>


I'm on 10gR2 on AIX with ASM. have DB_FILE_MULTIBLOCK_READ_COUNT=16 in spfile. but still see different block size for "db file scattered read" ranging from 2 to 16. Can someone explain why its ranging from 2-16? Shouldn't DBRC always be followed if it's set in SPFILE?

see below excerpts from 10046 trace file.

WAIT #3: nam='db file scattered read' ela= 48396 file#=61 block#=416 blocks=5 obj#=80135 tim=1526895870393
WAIT #3: nam='db file scattered read' ela= 8210 file#=61 block#=33717 blocks=4 obj#=80135 tim=1526895880210
WAIT #3: nam='db file scattered read' ela= 7306 file#=61 block#=52614 blocks=3 obj#=80135 tim=1526895897691
WAIT #3: nam='db file scattered read' ela= 8508 file#=61 block#=53030 blocks=16 obj#=80135 tim=1526896239141
WAIT #3: nam='db file scattered read' ela= 15903 file#=61 block#=53046 blocks=15 obj#=80135 tim=1526896258427
WAIT #3: nam='db file scattered read' ela= 921 file#=61 block#=53379 blocks=2 obj#=80135 tim=1526896507844

Thanks Received on Mon Jul 07 2008 - 16:19:00 CDT

Original text of this message