Re: DB CPU is much lower than CPU Time Reported by TOP SQL consumers
Date: Mon, 26 Nov 2012 00:26:31 +0100
Message-ID: <CAGyPXK6veGtpVhuZBB__SW0Ue-vFKxKCY1r1JNM8Xber5vb7-w_at_mail.gmail.com>
The difference you see IMO is coming from wait time in CPU run-queue - as Karl has already mentioned.
The reported value by oracle for CPU consumption of statement (or process) doesn't differentiate if the process was all the time on CPU or on-CPU, on-CPU-run-queue and then again on-CPU. Oracle just reports let say total <xzy>ms CPU-time.
Do you have OS statistics (OSWatcher for example) from this period to compare?
On Tue, Nov 13, 2012 at 9:00 PM, Ls Cheng <exriscer_at_gmail.com> wrote:
> Hi
> I also thought of that and in fact one statement was called by another but
> the rest doesnt seem the case:
>
> See following data and attention to the module, they are all different so
> cant be double counting:
>
>
>
> * CPU CPU per Elapsd
> Old
> Time (s) Executions Exec (s) %Total Time (s) Buffer Gets Hash
> Value
> ---------- ------------ ---------- ------ ---------- ---------------
> ----------
> 4407.08 20,294 0.22 51.6 10006.66 1,228,369,784
> 3703299877
> Module: JDBC Thin Client
>
> 3943.14 157,316 0.03 46.2 6915.60 1,034,202,723
> 1127338565
> Module: sel_ancomm_vss_06.tsk_at_c2aixprod (TNS V1-V3)
>
> 2358.20 269,711 0.01 27.6 4095.76 1,508,308,542
> 1995656981
> Module: sel_zuteiler_alert.tsk_at_c2aixprod (TNS V1-V3)
>
> 1305.21 9,932 0.13 15.3 2483.90 331,327
> 1310406159
> Module: sel_verwaltung.tsk_at_c2aixprod (TNS V1-V3)*
>
> These 4 statements already adds up to 12013 CPU Seconds and the DB CPU is
> 8464 seconds.
>
> Also look this text from top sql statmenet section:
>
> -> Total DB CPU (s): 8,539
> *-> Captured SQL accounts for 232.5% of Total DB CPU*
> -> SQL reported below exceeded 1.0% of Total DB CPU
>
> Capture SQL is 232% DB CPU! How can this be possible?
>
> Thanks
>
>
> --
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>
>
>
-- http://www.freelists.org/webpage/oracle-lReceived on Mon Nov 26 2012 - 00:26:31 CET