答复： Check if async_io is enabled at disk-level
- From: zhuchao@xxxxxxxxx
- To: sharmakdeep_oracle@xxxxxxxxx,oracle-l@xxxxxxxxxxxxx
- Date: Tue, 16 Sep 2008 14:54:34 +0000
I think what you have seen with nmon just confirms you are using kaio. If it is
using threaded aio then the aioserver will be used.
Truss should proves that. I am not sure what the system call is like on aix, on
solaris it is pwrite vs kaio(write...). Should be somrthing similar
Sent via BlackBerry by AT&T
-----Original Message-----
From: Deepak Sharma <sharmakdeep_oracle@xxxxxxxxx>
Date: Mon, 15 Sep 2008 21:39:09
To: <oracle-l@xxxxxxxxxxxxx>
Subject: Check if async_io is enabled at disk-level
Hi,
We are using ODM (Oracle Disk Manager) on one of our 10.2.0.3 DBs, and the
disk_asynch_io is TRUE in the database. I have also read that ODM supports
kernel asynchronous I/O. The platform is AIX 5.3
Using 'nmon' and choosing "A = Async I/O Servers", this is what we see :
Asynchronous-I/O-Processes
Total AIO processes= 100 Actually in use= 0
This might indicate that AIO is not happening at kernel-level.
How else can we verify if async I/O is actually happening at Kernel-level? We
could possibly truss the DB Writer process(es) and check for the kernel-level
calls for writes - what should we look for? Is it kiowrite() instead of plain,
write() ?
Thanks,
Deepak
Other related posts:
