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High CPU usage

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  • raven-worxR raven-worx

    @Ketan__Patel__0011 said in High CPU usage:

    run your applications in your system which are uses more than 70% CPU and also your application run 10 to 20 function working parallelly For continuously 2 or 3 days. that time it may be your system can be failed.

    now you are talking about faulty applications. Before you were talking about running the compiler.
    A faulty application may make your system unstable yes. But thats the fault of a badly programmed application then. Even if the system is out of memory the OS tries to solve it and terminates the application. The application should be fixed then.
    So the conclusion that 100% CPU means unstable system is still wrong. If the application is programmed correctly the machine can run for weeks with 100% CPU load.

    Ketan__Patel__0011K Offline
    Ketan__Patel__0011K Offline
    Ketan__Patel__0011
    wrote on last edited by
    #14

    @raven-worx

    again if 100% CPU uses at runtime when i perform any operation that time i can deal with it but at compile time it may be problem comes from the compiler or may be my Qt Version is unstable

    ->My Qt Version Is : 5.12.3

    JonBJ O 2 Replies Last reply
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    • Ketan__Patel__0011K Ketan__Patel__0011

      @raven-worx

      again if 100% CPU uses at runtime when i perform any operation that time i can deal with it but at compile time it may be problem comes from the compiler or may be my Qt Version is unstable

      ->My Qt Version Is : 5.12.3

      JonBJ Online
      JonBJ Online
      JonB
      wrote on last edited by
      #15

      @Ketan__Patel__0011
      Your Qt version is probably not relevant. You are reporting the C++ compiler taking a lot of time. And since you say

      i was create one qt application And i Used Some image Processing Library in my application and used it's functions

      I can only guess that your image processing library --- the header files you include from it --- are so "complex" that it just takes the compiler a long time to compile code which includes them.

      Please confirm that if you let it take whatever time it wants your compile/link do complete successfully? In which case I wouldn't worry about it, it is what it is. If on the other hand it fails to come to a successful conclusion, then that would be a different matter....

      Ketan__Patel__0011K 1 Reply Last reply
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      • Ketan__Patel__0011K Ketan__Patel__0011

        @raven-worx

        again if 100% CPU uses at runtime when i perform any operation that time i can deal with it but at compile time it may be problem comes from the compiler or may be my Qt Version is unstable

        ->My Qt Version Is : 5.12.3

        O Offline
        O Offline
        ollarch
        wrote on last edited by
        #16

        @Ketan__Patel__0011
        When you run the application the complier does nothing. It have finished the work and it have generated an executable file.
        Are you sure that the application is not doing anything?
        Could you try to comment the processing library include files and run the application again?

        Ketan__Patel__0011K 1 Reply Last reply
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        • JonBJ JonB

          @Ketan__Patel__0011
          Your Qt version is probably not relevant. You are reporting the C++ compiler taking a lot of time. And since you say

          i was create one qt application And i Used Some image Processing Library in my application and used it's functions

          I can only guess that your image processing library --- the header files you include from it --- are so "complex" that it just takes the compiler a long time to compile code which includes them.

          Please confirm that if you let it take whatever time it wants your compile/link do complete successfully? In which case I wouldn't worry about it, it is what it is. If on the other hand it fails to come to a successful conclusion, then that would be a different matter....

          Ketan__Patel__0011K Offline
          Ketan__Patel__0011K Offline
          Ketan__Patel__0011
          wrote on last edited by
          #17

          @JonB

          Thanks for you reply

          i am used Same Library in Microsoft visual studio 2015 and i create new project in Microsoft visual studio 2015 and i didn't get Any Issus my project Compile Successfully
          and when i start compiling my visual studio c++ project that time my System used less than 20% Of CPU.

          and i think in Qt MSVC 2015 Kit and Microsoft Visual Studio 2015 are used Same Compiler for C++

          O 1 Reply Last reply
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          • O ollarch

            @Ketan__Patel__0011
            When you run the application the complier does nothing. It have finished the work and it have generated an executable file.
            Are you sure that the application is not doing anything?
            Could you try to comment the processing library include files and run the application again?

            Ketan__Patel__0011K Offline
            Ketan__Patel__0011K Offline
            Ketan__Patel__0011
            wrote on last edited by
            #18

            @ollarch

            Thanks for your Reply

            I am faced this problem Many Time ,but i didn't get any solution
            if i used any library or not

            1 Reply Last reply
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            • Ketan__Patel__0011K Ketan__Patel__0011

              @JonB

              Thanks for you reply

              i am used Same Library in Microsoft visual studio 2015 and i create new project in Microsoft visual studio 2015 and i didn't get Any Issus my project Compile Successfully
              and when i start compiling my visual studio c++ project that time my System used less than 20% Of CPU.

              and i think in Qt MSVC 2015 Kit and Microsoft Visual Studio 2015 are used Same Compiler for C++

              O Offline
              O Offline
              ollarch
              wrote on last edited by
              #19

              @Ketan__Patel__0011
              You are mixing compilation times and execution times. Where is your problem? When compiling or when running? And wich is the problem? High CPU usage? When comiling as more CPU used less time to compile and when running it will depend on what is your application doing.
              About faulty applications... If it faults it has a bug so you have to find it and remove it.

              JonBJ Ketan__Patel__0011K 2 Replies Last reply
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              • O ollarch

                @Ketan__Patel__0011
                You are mixing compilation times and execution times. Where is your problem? When compiling or when running? And wich is the problem? High CPU usage? When comiling as more CPU used less time to compile and when running it will depend on what is your application doing.
                About faulty applications... If it faults it has a bug so you have to find it and remove it.

                JonBJ Online
                JonBJ Online
                JonB
                wrote on last edited by JonB
                #20

                @ollarch
                I believe @Ketan__Patel__0011 has consistently only reported compilation/link timings, I don't see where you see he might be reporting runtime execution time?

                If he says that outside of Qt Creator it compiles with 20% CPU while inside it is 90% that does sound a touch strange.... It looks like it is the Microsoft Compiler Driver which is taking the time....

                O 1 Reply Last reply
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                • O ollarch

                  @Ketan__Patel__0011
                  You are mixing compilation times and execution times. Where is your problem? When compiling or when running? And wich is the problem? High CPU usage? When comiling as more CPU used less time to compile and when running it will depend on what is your application doing.
                  About faulty applications... If it faults it has a bug so you have to find it and remove it.

                  Ketan__Patel__0011K Offline
                  Ketan__Patel__0011K Offline
                  Ketan__Patel__0011
                  wrote on last edited by
                  #21

                  @ollarch

                  No i am not talking about execution time

                  Capture_2.PNG

                  My Problem is High CPU Uses When I start to Build My Project

                  And Tell me one think you never faced this problem ?

                  1 Reply Last reply
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                  • JonBJ JonB

                    @ollarch
                    I believe @Ketan__Patel__0011 has consistently only reported compilation/link timings, I don't see where you see he might be reporting runtime execution time?

                    If he says that outside of Qt Creator it compiles with 20% CPU while inside it is 90% that does sound a touch strange.... It looks like it is the Microsoft Compiler Driver which is taking the time....

                    O Offline
                    O Offline
                    ollarch
                    wrote on last edited by
                    #22

                    @JonB
                    Maybe QtCreator is uning multiprocessor compiling while Visual Studio is not. The Intel i3-3220 has 4 core threads, so 20~25 CPU usage during compilation sounds like only one core is used.
                    On Visual Studio check the "C/C++" options , section "All options" parameter "Additional options", and set "/MP4" to it. It will use 4 cores on compilation.

                    Ketan__Patel__0011K 1 Reply Last reply
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                    • O ollarch

                      @JonB
                      Maybe QtCreator is uning multiprocessor compiling while Visual Studio is not. The Intel i3-3220 has 4 core threads, so 20~25 CPU usage during compilation sounds like only one core is used.
                      On Visual Studio check the "C/C++" options , section "All options" parameter "Additional options", and set "/MP4" to it. It will use 4 cores on compilation.

                      Ketan__Patel__0011K Offline
                      Ketan__Patel__0011K Offline
                      Ketan__Patel__0011
                      wrote on last edited by
                      #23

                      @ollarch

                      Thanks for your reply and your suggestion

                      i will try your idea But I am not developing Software in visual studio.
                      i am developing software in QT, currently am working on this problem.
                      doesn't matter why Microsoft visual studio 2015 not use more than 20-25% of CPU

                      My higher priority is to solve this problem in QT

                      or If you get any other idea or any other solution for it than please drop your answer or suggestion here
                      Again Thanks You So Much

                      1 Reply Last reply
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                      • O Offline
                        O Offline
                        ollarch
                        wrote on last edited by
                        #24

                        I think that as the othre users suggest you, this is not a problem. QtCreateor is using all CPUs to reduce compilation time. It's the expected behaviour.

                        Ketan__Patel__0011K 1 Reply Last reply
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                        • O ollarch

                          I think that as the othre users suggest you, this is not a problem. QtCreateor is using all CPUs to reduce compilation time. It's the expected behaviour.

                          Ketan__Patel__0011K Offline
                          Ketan__Patel__0011K Offline
                          Ketan__Patel__0011
                          wrote on last edited by
                          #25

                          @ollarch

                          Thanks For You Reply

                          Is there Any Mention in any QT Documentation or any other where ?

                          B 1 Reply Last reply
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                          • Ketan__Patel__0011K Ketan__Patel__0011

                            @ollarch

                            Thanks For You Reply

                            Is there Any Mention in any QT Documentation or any other where ?

                            B Offline
                            B Offline
                            Bonnie
                            wrote on last edited by
                            #26

                            @Ketan__Patel__0011
                            For MSVC builds, Qt uses jom instead of nmake, to build in parallel, use more CPU and speed up the building.
                            You can refer to:
                            https://wiki.qt.io/Jom
                            https://www.qt.io/blog/2009/03/27/speeding-up-visual-c-qt-builds

                            A 1 Reply Last reply
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                            • JKSHJ Offline
                              JKSHJ Offline
                              JKSH
                              Moderators
                              wrote on last edited by
                              #27

                              (Side discussion forked to https://forum.qt.io/topic/119207/relationships-between-qmake-make-nmake-jom-and-the-compiler )

                              Qt Doc Search for browsers: forum.qt.io/topic/35616/web-browser-extension-for-improved-doc-searches

                              1 Reply Last reply
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