Re: Async IO on Oracle 9.2.0.5

Krispyqube wrote:
> 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
>

It has been backported to 2.4 too.

By the way: what distro are you using?

> 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
>
>

You need to relink with:

oracle_at_linux > cd $ORACLE_HOME/rdbms/lib
oracle_at_linux > make PL_ORALIBS=-laio -f ins_rdbms.mk async_on
oracle_at_linux > make PL_ORALIBS=-laio -f ins_rdbms.mk ioracle

note the PL_ORALIBS=-laio

http://www.gesinet.it/oracle/asincio.html

> 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
>

check with:

cat /proc/slabinfo | grep kio

(if the first three numbers of every line contain zero then async i/o is not working.

regards

-- 
Fabrizio Magni

fabrizio.magni_at_mycontinent.com

replace mycontinent with europe