List Top 5 I/O sessions in last 2 minutes

From: Sean Zhang <sean_at_cnfei.com>
Date: Mon, 06 Dec 1999 17:38:34 GMT
Message-ID: <uwS24.12574$W%.35989819@firenze.visi.net>

Hello, Everyone,

Our environment: Oracle 8i on Sun Sparc Solaris 2.6.

Problem: Sometimes our system stands still because

                 All CPUs are waiting for disk I/O, and yet after
                 a few minutes the system goes to normal
                 again. I know I can use the table V$sess_io to list
                 all I/O by session , but these numbers are
                 cumulative results since the session begins, over
                a period of time, all these I/O numbers seems
                 averaged out themselves and are not much different by each
session,
               Question: HOW can I find the top 5 I/O sessions , say,
                  just in last 2 minutes? Can I get the results by using a

simple SQL script?

Any suggestions and advises are greatly appreciated.

Sean Zhang
mailto:sean_at_cnfei.com Received on Mon Dec 06 1999 - 11:38:34 CST