Hi

We are trying to figure if oracle is indeed using async io

there are two articles/notes i referred to in the process and of course
the metalink. We did relink the Oracle kernel

1. http://download-east.oracle.com/oowsf2004/1449_wp.pdf  See page 14

2. http://www.grabinar.com/simon/aio.html

i am still not sure if the server is doing async io and the other issue
is when we run quries on the DB i see a lot of Io waits
Checks we have done. The OS is enabled with async io looks like its the
threaded aysnc io since kernel io is only in 2.6 +
we are using

Linux extapp1 2.4.21-27.ELsmp #1 SMP Wed Dec 1 21:59:02 EST 2004 i686
i686 i386 GNU/Linux

Oracle 9.2.0.5 with the aio related patches

nm $ORACLE_HOME/bin/oracle | grep io_getevent
        U io_getevents@@LIBAIO_0.1

ran a sql query which dd full table scans
and trace the pid with
strace -p pid

Among other systems calls you will see either:
a. synchronous calls
         read(3, "783|37567799|213483944|2004-10-1"..., 4096) = 4096
b. asynchronous calls
    io_submit(0xb6a93000, 0x1, 0xbfff236c) = 1
    io_submit(0xb6a93000, 0x1, 0xbfff236c) = 1
    io_getevents(0xb6a93000, 0x1, 0x400, 0xbffeb794,

i am only seeing case a. read

On lthe linux box
rpm -q --whatprovides libaio
libaio-0.3.96-5

and its enabled
Oops i forgot Oracle is also enabled with the asynch io parameters
filesystemio_options=asynch
disk_asynch_io=true

is this a fair test to confirm aio is happening or is there any other
definitive method to confirm if we are indeed using asynch io

thanks for any help

regds
Kris