> I’m not sure how to calcaulate the number for the cpu usage for the db i’m currently on:

Two corrections and then it should work:

1) You divided v$sys_time_model.value by 100000 instead of 1000000.

2) If you want a percentage based on the number of CPUs, you should use “(l_t2.instance_cpu_time-l_t1.instance_cpu_time)/l_num_cpus/p_interval” to initialize l_out.

HTH
Chris

I have tried to combine with V$SYS_TIME_MODEL, but I’m not sure how to calcaulate the number for the cpu usage for the db i’m currently on:

 

FOR i IN 1..p_count+1
  LOOP
    SELECT systimestamp, sum(decode(stat_name,'IDLE_TIME', value, NULL)) as idle_time,
           sum(decode(stat_name,'USER_TIME', value, NULL)) as user_time,
           sum(decode(stat_name,'SYS_TIME', value, NULL)) as sys_time,
           sum(decode(stat_name,'IOWAIT_TIME', value, NULL)) as iowait_time,
           sum(decode(stat_name,'NICE_TIME', value, NULL)) as nice_time
    INTO l_t2.date_time_to, l_t2.idle_time, l_t2.user_time, l_t2.sys_time, l_t2.iowait_time, l_t2.nice_time
    FROM v$osstat
    WHERE stat_name in ('IDLE_TIME','USER_TIME','SYS_TIME','IOWAIT_TIME','NICE_TIME');

    select value/100000
    into l_t2.instance_cpu_time
    from  V$SYS_TIME_MODEL
    where stat_name = 'DB CPU';

    l_out := osstat_record(l_t1.date_time_from, systimestamp,
                           (l_t2.idle_time-l_t1.idle_time)/l_num_cpus/p_interval,
                           (l_t2.user_time-l_t1.user_time)/l_num_cpus/p_interval,
                           (l_t2.sys_time-l_t1.sys_time)/l_num_cpus/p_interval,
                           (l_t2.iowait_time-l_t1.iowait_time)/l_num_cpus/p_interval,
                           (l_t2.nice_time-l_t1.nice_time)/l_num_cpus/p_interval,
                           ((l_t2.instance_cpu_time-l_t1.instance_cpu_time)/p_interval));

    l_total := l_out.idle_time+l_out.user_time+l_out.sys_time+l_out.iowait_time+nvl(l_out.nice_time,0);

    if l_out.user_time > 0 then
       l_instance := (l_out.instance_cpu_time*100)/l_total;
    else
       l_instance := 0;
    end if;

    if i > 1 then
    PIPE ROW(osstat_record(l_t1.date_time_to, systimestamp,
                           trunc((l_out.idle_time/l_total*100),p_dec),
                           trunc((l_out.user_time/l_total*100),p_dec),
                           trunc((l_out.sys_time/l_total*100),p_dec),
                           trunc((l_out.iowait_time/l_total*100),p_dec),
                           trunc((l_out.nice_time/l_total*100),p_dec),
                           trunc(l_instance,p_dec)));
    end if; 

       lout := osstat_record(systimestamp,
                           (l_t2.idle_time-l_t1.idle_time),
                           (l_t2.user_time-l_t1.user_time),
                           (l_t2.sys_time-l_t1.sys_time),
                           (l_t2.iowait_time-l_t1.iowait_time),
                           (l_t2.nice_time-l_t1.nice_time));

DATE_TIM USER_TIME NICE_TIME SYS_TIME IOWAIT_TIME IDLE_TIME
-------- --------- --------- -------- ----------- ---------
05:02:18      6.89      0.00     1.95        0.00     91.15
05:02:19      7.09      0.00     0.73        0.00     92.19
05:02:20      6.68      0.00     0.55        0.00     92.77
05:02:22      6.67      0.00     0.61        0.00     92.72
05:02:23      6.85      0.00     0.73        0.00     92.41

It makes sense since you’re dividing each value by the the sum of the values later to get the percentage.

Cheers
Ivan

Yes, I get that as far as l_num_cpus go but why p_interval? You can divide by 42 or a million or any other number and the script will still produce correct result with any input values.

Cheers
Ivan

First of all, thank you very much for your feedback.

About your question… I divide by l_num_cpus and p_interval because I want to have a percentage that sums up to 100% and not the absolute values. Ok?

Cheers,
Chris

There’s this one thing I can’t seem to wrap my head around: why do you divide by p_interval in the lout := osstat_record(systimestamp,…) -statement?

Best regards
Ivan Bajon

Wonderful tool. It works fine on my Solaris box but on 10.2.0.4/Win2003(64bit) I get all blanks. This can be remedied by replacing the NULLs with 0s in the select statement:

SELECT sum(decode(stat_name,’IDLE_TIME’, value, 0)) as idle_time,
sum(decode(stat_name,’USER_TIME’, value, 0)) as user_time,
sum(decode(stat_name,’SYS_TIME’, value, 0)) as sys_time,
sum(decode(stat_name,’IOWAIT_TIME’, value, 0)) as iowait_time,
sum(decode(stat_name,’NICE_TIME’, value, 0)) as nice_time
INTO l_t2.idle_time, l_t2.user_time, l_t2.sys_time, l_t2.iowait_time, l_t2.nice_time
FROM sys.v_$osstat
WHERE stat_name in (‘IDLE_TIME’,'USER_TIME’,'SYS_TIME’,'IOWAIT_TIME’,'NICE_TIME’);

Best regards
Ivan Bajon