Mladen, I guess the rdbms kernel will be passing the startblock-stop block addresses and will be passing to the readv (or pread?) system calls. A single multiblock read can not read two different sets (!) of contiguos blocks.. Or I am thinking in the different direction??
Best Regards, K Gopalakrishnan -----Original Message----- Mladen Sent: Monday, March 17, 2003 7:45 AM To: Multiple recipients of list ORACLE-L How can you tell that DB_FILE_MULTIBLOCK_READ will not span extents? I was unable to confitrm that on Metalink. > -----Original Message----- > From: Hemant K Chitale [mailto:[EMAIL PROTECTED] > Sent: Monday, March 17, 2003 9:44 AM > To: Multiple recipients of list ORACLE-L > Subject: Re: db file scattered read > > > > If 14706+3 is one extent and another extent begins at 14710, > it will NOT read > 14706+8. A DB_FILE_MULTIBLOCK_READ will not span extents. > Hemant > > At 09:04 AM 14-03-03 -0800, you wrote: > >Here is a part of trace file . I am finding that oracle is > trying to read > >8 or 3 or 7 blocks at a time . But block numbers are all > sequential i.e. > >it will read 3 blocks starting from 14706 and then 8 blocks > starting from > >14710 ( 14706+3 ). Why it doesn't read 8 blcoks always it > multi_block_read > >is set to 8 ? Any Idea . > >Also what is ela=1 ,does it mean elapsed time is 1 sentisec ? > > > > > > > >WAIT #32: nam='db file scattered read' ela= 0 p1=4 p2=14706 p3=3 > >WAIT #32: nam='db file scattered read' ela= 1 p1=4 p2=14710 p3=8 > >WAIT #32: nam='db file scattered read' ela= 2 p1=4 p2=14718 p3=8 > >WAIT #32: nam='db file scattered read' ela= 0 p1=4 p2=14727 p3=3 > >WAIT #32: nam='db file scattered read' ela= 0 p1=4 p2=14731 p3=7 > >WAIT #32: nam='db file scattered read' ela= 1 p1=4 p2=14739 p3=3 > >WAIT #32: nam='db file scattered read' ela= 1 p1=4 p2=14744 p3=8 > >WAIT #32: nam='db file scattered read' ela= 1 p1=4 p2=129784 p3=8 > > > > > >Thanks > >-ak > > Hemant K Chitale > My personal web site is : http://hkchital.tripod.com > > > -- > Please see the official ORACLE-L FAQ: http://www.orafaq.net > -- > Author: Hemant K Chitale > INET: [EMAIL PROTECTED] > > Fat City Network Services -- 858-538-5051 http://www.fatcity.com > San Diego, California -- Mailing list and web hosting services > --------------------------------------------------------------------- > To REMOVE yourself from this mailing list, send an E-Mail message > to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in > the message BODY, include a line containing: UNSUB ORACLE-L > (or the name of mailing list you want to be removed from). You may > also send the HELP command for other information (like subscribing). > -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Gogala, Mladen INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: K Gopalakrishnan INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
