Oracle I/O Per Second (IOPS) Tips

Question:  How can I calculate my Oracle I/O per second?  I know that stats$sysstat can compute total I/O, but I need to calculate my I/O per second using the AWR tables.

Answer:  You can use the dba_hist_sysstat table to compute I/O per second (IOPS). 

If you don’t want to write your own I/O per second script, see the Oracle script collection.

select
    to_char(sn.end_interval_time,'yyyymmddhh24') the_date,
    sum(decode(sn2.startup_time,sn3.startup_time,(newreads.value-            oldreads.value),newreads.value)) reads,
    sum(decode(sn2.startup_time,sn3.startup_time,(newwrites.value-            oldwrites.value),newwrites.value)) writes,
    (sum(decode(sn2.startup_time,sn3.startup_time,(newreads.value-            oldreads.value),newreads.value)))+
    (sum(decode(sn2.startup_time,sn3.startup_time,(newwrites.value-            oldwrites.value),newwrites.value)))
total
from
    dba_hist_sysstat  oldreads,
    dba_hist_sysstat  newreads,
    dba_hist_sysstat  oldwrites,
    dba_hist_sysstat  newwrites,
    dba_hist_snapshot sn,
    dba_hist_snapshot sn2,
    dba_hist_snapshot sn3
where

See Code Depot for Full Script

group by
       to_char(sn.end_interval_time,'yyyymmddhh24')
order by
       to_char(sn.end_interval_time,'yyyymmddhh24')
;

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