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      • 30. Re: excessive LOCAL=NO oracle processes
        Billy~Verreynne
        I still have an issue with considering 100% as "normal".

        Any gamer will tell you that running any modern FPS will hit the CPU hard and peg it at 100%. And that will be the case from an old CPU to a modern dual core CPU. So 100% on both and everything is fine - no problem? The game could be everything but playable on the older CPU.

        Which begs the question - is 100% optimal use (i.e. is the system coping) or does demand exceed the power of the CPU?

        Glib statements like "this is every day normal stuff" does not cut it - as it implies there is no problem with 100% CPU utilisation.

        Wrong! There could be MAJOR problems with 100% CPU utilisation. Just like there could be major problems with 0% CPU utilisation.
        • 31. Re: excessive LOCAL=NO oracle processes
          ji li
          Maybe what needs to be clarified is "for how long of a time are we talking about"?

          If your database is causing 100% CPU utilization most of the time, then I agree that its probably starved for more CPU (please correct me if I am wrong).

          But if your CPU is only at 100% when you run occasional processes that demand the extra processing power, then it should not be an issue, especially if you have multiple CPUs. And on that note, if you are running Oracle on a server with only one CPU that is constantly hitting 100% utilization, then it is time to add more horsepower, more CPUs, and probably other hardware/software resources as well.

          Ji li
          • 32. Re: excessive LOCAL=NO oracle processes
            311441
            Hi Ji

            What if you had a 6 CPU system with CPU utilisation constantly at 100%.

            Would you describe your system as being in an "optimal" state ?

            When someone suggests ""BTW, it's normal to see CPU at 100%, it's designed that way.", how long do you consider it normal before you start thinking actually things may not be that optimal after all ?

            Cheers

            Richard Foote
            http://richardfoote.wordpress.com/
            • 33. Re: excessive LOCAL=NO oracle processes
              ji li
              Agreed... but again, I'd still have to ask for "how long?".

              At my last job, I ran 8 dual core CPUs on a clustered Sun V490 rac system with 16 Gb of RAM and occasinally saw our CPU top out (although extremely rare to see all CPUs that busy). I had literally 12,000 to 16,000 simultaneous users connected to the main database using connection pooling (websphere) from a middle tier server. The Websphere constantly kept the CPUs pegged on the middle tier, but that was IBMs software problem, not my databases on my servers.

              (I may be mistaken that I may have only had 4 dual core CPUs per box... can't remember which one had which).

              ji li
              • 34. Re: excessive LOCAL=NO oracle processes
                Billy~Verreynne
                One cannot just look at CPU utilisation. And nor does a 50% or 0% utilisation mean "no problem" whereas 100% means "potential problem". Nor does the number of CPUs play the only role.

                A single CPU pegged at 100% can be of major concern on a SMP box with 64 CPUs. As a single process runs on a single CPU - so despite the other 63 CPUs being mostly idle, there can be a performance concern with that single process.

                The utilisation alone is meaningless. And if there has to be a response to the statement "my server shows 100% CPU utilisation", then it is not "This is every day normal stuff". The correct response is "So what!?". It has to be interpreted within the right context.

                That said, a 100% utilisation is more of a potential concern than 50% or 0% utilisation ito a possible CPU bottleneck. And that is an acceptable re-action, much more so than re-acting to 100% utilisation stating this is normal or optimal and to ignore it.

                And that is the basic issue for me - and what believe some posters have tried to raise here.
                • 35. Re: excessive LOCAL=NO oracle processes
                  ji li
                  Agreed... thank you for your clarification.
                  • 36. Re: excessive LOCAL=NO oracle processes
                    311441
                    That said, a 100% utilisation is more of a
                    potential concern than 50% or 0% utilisation ito a
                    possible CPU bottleneck. And that is an acceptable
                    re-action, much more so than re-acting to 100%
                    utilisation stating this is normal or optimal and to
                    ignore it.

                    And that is the basic issue for me - and what believe
                    some posters have tried to raise here.
                    Hi Billy

                    Exactly, well said.

                    Of course, "any real-world working DBA would know this . . . . "

                    Cheers ;)

                    Richard Foote
                    http://richardfoote.wordpress.com/
                    • 37. Re: excessive LOCAL=NO oracle processes
                      ji li
                      It seems we are all in agreement...

                      :-)
                      • 38. Re: excessive LOCAL=NO oracle processes
                        311441
                        Hi Ji

                        Not quite.

                        I can't agree with anyone who claims "it's normal to see CPU at 100%, it's designed that way" ...

                        Cheers ;)

                        Richard Foote
                        http://richardfoote.wordpress.com/
                        • 39. Re: excessive LOCAL=NO oracle processes
                          Billy~Verreynne
                          > Of course, "any real-world working DBA would know this . . . . "

                          Yeah.. not sure if I qualify. Just how much should a "real-world working DBA" be able to bench press?
                          PS. And my answer to anyone saying what this has to do with being a DBA?: 
                              A. Exactly!
                          ;-)
                          • 40. Re: excessive LOCAL=NO oracle processes
                            311441
                            Hi Billy

                            LOL !!!!

                            Cheers

                            Richard Foote
                            http://richardfoote.wordpress.com/
                            • 41. Re: excessive LOCAL=NO oracle processes
                              311441
                              Hi Don

                              Still waiting for my lesson ...

                              Based on the report you posted, can you please show me what the "CPU Load" equates to ?

                              Can you then please show me what the "CPU utilisation" equates to and how it differs?

                              Finally, can you please show me how the CPU in the report is at the "usual" 100% that it's designed to be if this is only meant to be some kinda exception report ?

                              Cheers ;)

                              Richard Foote
                              http://richardfoote.wordpress.com/
                              • 42. Re: excessive LOCAL=NO oracle processes
                                108476
                                Still waiting for my lesson ...
                                Good luck with that. . . . .

                                You insulted me the last time I tried to correct one of your misconceptions, and you were dead wrong, to boot.
                                • 43. Re: excessive LOCAL=NO oracle processes
                                  311441
                                  Hi Don

                                  Knew you couldn't ;)

                                  Cheers

                                  Richard Foote
                                  http://richardfoote.wordpress.com/
                                  • 44. Re: excessive LOCAL=NO oracle processes
                                    108476
                                    Knew you couldn't ;)
                                    Yup, nobody can teach someone who is not willing to listen and learn . . . .

                                    You just want to argue . . .
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