Re: directio and async io on redhat linux 3 and oracle 9i

hrishy_at_gmail.com apparently said,on my timestamp of 7/05/2005 4:54 PM:

> I know of one way to do it is tracing the dbwr and seeing whether fopen
> call is with o_direct flags.But the strange thing is when i say
>
> sqlplus>conn /as sysdba;
>
> sqlplus>oradebug setospid <<ospid-of-dbwriter>>
>
> no trace file is being produced.Can somebody tell me what magic needs
> to be done by me :-)

Well, dunno about oradebug. But with strace all you have to do is use it to call sqlplus and then start the database. Use the "-ff" and "-f" options so you get one trace file per spawned process and "-e trace=open, read,write": then it's dirt easy to find the dbwr trace file and the wanted info in it.

And no, in RHAS I haven't yet been able to see O_DIRECT being used anywhere. I suspect it can't be used on file system datafiles in 9i anyway. At least, it's not in any of the availability matrixes in metaclick. 10g might be a different kettle though. Ah yes: if you run 9.2.0.6, make sure you apply the required metaclick patch to get aio to work. Otherwise it says it's there, but it'll be broken. DAMHIKT...

-- 
Cheers
Nuno Souto
in sunny Sydney, Australia
wizofoz2k_at_yahoo.com.au.nospam