David is right, -t just filters out specfic calls otherwise the truss output can be a bit too much some times. Richard -----Original Message----- From: David Green [mailto:thump@xxxxxxxxxxxxxxxx] Sent: Tue 5/4/2004 11:27 PM To: oracle-l@xxxxxxxxxxxxx Cc: Subject: RE: aio on sun ufs problem -----Original Message----- From: oracle-l-bounce@xxxxxxxxxxxxx = [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of zhu chao Sent: Tuesday, May 04, 2004 5:00 AM To: oracle-l@xxxxxxxxxxxxx Subject: aio on sun ufs problem Hi friends: While reading the following paper: http://de.sun.com/Partner/Softwarepartner/Oracle/Technik/pdf/oracle_on_su= n.p df It says for oracle 8.1.7/ufs, aio is by default disabled. We must = enable it explictly with _filesystemio_options=3Dasynch. Is it true? For aio on = raw device/QuickIO, we can see truss -t kaio -p dbwr to verify it, for aio = on filesystem, how to verify it then? --- Aio on solaris is enabled by default if you use disk_asynch_io =3D true. = You will see a failed system call to kaio and then pread pwrite processes = spawn to simulate aio via light weight threaded processing. You can verify this in the same way using truss against dbwr. I'm not = sure what -t does, but if you just truss on dbwr process you will see the behavior. I personally feel that dbwr_io_slaves when weighed against = these facts are better suted at simulating aio than the light weight threaded processes. - David ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- -- Binary/unsupported file stripped by Ecartis -- -- Type: application/ms-tnef -- File: winmail.dat ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx put 'unsubscribe' in the subject line. -- Archives are at //www.freelists.org/archives/oracle-l/ FAQ is at //www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------