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  1. JDK
  2. JDK-8265836

OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

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        Created on behalf of albert.th@alibaba-inc.com
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        OperatingSystemImpl.getCpuLoad() may return 1.0 in a container, even though the CPU load is obviously below 100%.

        We created a 5-core container and run 4 "while (true)" loops in the container. OperatingSystemImpl.getCpuLoad() returned 1.0, which is incorrect (0.8 is correct).
        "systemLoad" in getCpuLoad() is exactly 4.0 before "systemLoad = Math.min(1.0, systemLoad);". The problem is caused by using the elapsed time (specified by "cpu.cfs_period_us") instead of the total CPU time (specified by "cpu.cfs_quota_us"). Therefore, it is more reasonable to divide cpu usage time by "quotaNanos" instead of "elapsedNanos".

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8268048 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8269874 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8272221 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8282613 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8284595 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8282708 OperatingSystemImpl.getCpuLoad() returns incorrect CPU load inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Closed
            relates to

            Bug - A problem which impairs or prevents the functions of the product. JDK-8268098 jdk.CPULoad event reports incorrect CPU usage inside a container

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Closed

            Bug - A problem which impairs or prevents the functions of the product. JDK-8268103 JNI functions incorrectly return a double after JDK-8265836

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Bug - A problem which impairs or prevents the functions of the product. JDK-8269851 OperatingSystemMXBean getProcessCpuLoad reports incorrect process cpu usage in containers

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved
            links to

            Commit Commit openjdk/jdk11u-dev/37f36d5c

            Commit Commit openjdk/jdk/ef368b32

            Review Review openjdk/jdk11u-dev/20

            Review Review openjdk/jdk/3656

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                sgehwolf Severin Gehwolf
                yyang Yi Yang
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