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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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/*

 * @test

 * @summary Test JVM's CPU resource awareness when running inside docker container

 * @requires docker.support

 * @library /test/lib

 * @modules java.base/jdk.internal.misc

 *          java.management

 *          jdk.jartool/sun.tools.jar

 * @run driver TestCPUAwareness

 */

import java.util.List;

import jdk.test.lib.containers.docker.DockerRunOptions;

import jdk.test.lib.containers.docker.DockerTestUtils;

public class TestCPUAwareness {

    private static final String imageName = Common.imageName("cpu");

    private static final int availableCPUs = Runtime.getRuntime().availableProcessors();

    public static void main(String[] args) throws Exception {

        if (!DockerTestUtils.canTestDocker()) {

            return;

        }

        System.out.println("Test Environment: detected availableCPUs = " + availableCPUs);

        DockerTestUtils.buildJdkDockerImage(imageName, "Dockerfile-BasicTest", "jdk-docker");

        try {

            // cpuset, period, shares, expected Active Processor Count

            testComboWithCpuSets();

            // cpu shares - it should be safe to use CPU shares exceeding available CPUs

            testCpuShares(256, 1);

            testCpuShares(2048, 2);

            testCpuShares(4096, 4);

            // leave one CPU for system and tools, otherwise this test may be unstable

            int maxNrOfAvailableCpus =  availableCPUs - 1;

            for (int i=1; i < maxNrOfAvailableCpus; i = i * 2) {

                testCpus(i, i);

            }

            // If ActiveProcessorCount is set, the VM should use it, regardless of other

            // container settings, host settings or available CPUs on the host.

            testActiveProcessorCount(1, 1);

            testActiveProcessorCount(2, 2);

            // cpu quota and period

            testCpuQuotaAndPeriod(50*1000, 100*1000);

            testCpuQuotaAndPeriod(100*1000, 100*1000);

            testCpuQuotaAndPeriod(150*1000, 100*1000);

            testCpuQuotaAndPeriod(400*1000, 100*1000);

        } finally {

            DockerTestUtils.removeDockerImage(imageName);

        }

    }

    private static void testComboWithCpuSets() throws Exception {

        String cpuSetStr = CPUSetsReader.readFromProcStatus("Cpus_allowed_list");

        System.out.println("cpuSetStr = " + cpuSetStr);

        if (cpuSetStr == null) {

            System.out.printf("The cpuset test cases are skipped");

        } else {

            List<Integer> cpuSet = CPUSetsReader.parseCpuSet(cpuSetStr);

            // Test subset of cpuset with one element

            if (cpuSet.size() >= 1) {

                String testCpuSet = CPUSetsReader.listToString(cpuSet, 1);

                testAPCCombo(testCpuSet, 200*1000, 100*1000,   4*1024, true, 1);

            }

            // Test subset of cpuset with two elements

            if (cpuSet.size() >= 2) {

                String testCpuSet = CPUSetsReader.listToString(cpuSet, 2);

                testAPCCombo(testCpuSet, 200*1000, 100*1000, 4*1024, true, 2);

                testAPCCombo(testCpuSet, 200*1000, 100*1000, 1023,   true, 2);

                testAPCCombo(testCpuSet, 200*1000, 100*1000, 1023,   false,  1);

            }

            // Test subset of cpuset with three elements

            if (cpuSet.size() >= 3) {

                String testCpuSet = CPUSetsReader.listToString(cpuSet, 3);

                testAPCCombo(testCpuSet, 100*1000, 100*1000, 2*1024, true, 1);

                testAPCCombo(testCpuSet, 200*1000, 100*1000, 1023,   true, 2);

                testAPCCombo(testCpuSet, 200*1000, 100*1000, 1023,   false,  1);

            }

        }

    }

    private static void testActiveProcessorCount(int valueToSet, int expectedValue) throws Exception {

        Common.logNewTestCase("Test ActiveProcessorCount: valueToSet = " + valueToSet);

        DockerRunOptions opts = Common.newOpts(imageName)

            .addJavaOpts("-XX:ActiveProcessorCount=" + valueToSet, "-Xlog:os=trace");

        Common.run(opts)

            .shouldMatch("active processor count set by user.*" + expectedValue);

    }

    private static void testCpus(int valueToSet, int expectedTraceValue) throws Exception {

        Common.logNewTestCase("test cpus: " + valueToSet);

        DockerRunOptions opts = Common.newOpts(imageName)

            .addDockerOpts("--cpus", "" + valueToSet);

        Common.run(opts)

            .shouldMatch("active_processor_count.*" + expectedTraceValue);

    }

    // Expected active processor count can not exceed available CPU count

    private static int adjustExpectedAPCForAvailableCPUs(int expectedAPC) {

        if (expectedAPC > availableCPUs) {

            expectedAPC = availableCPUs;

            System.out.println("Adjusted expectedAPC = " + expectedAPC);

        }

        return expectedAPC;

    }

    private static void testCpuQuotaAndPeriod(int quota, int period)

        throws Exception {

        Common.logNewTestCase("test cpu quota and period: ");

        System.out.println("quota = " + quota);

        System.out.println("period = " + period);

        int expectedAPC = (int) Math.ceil((float) quota / (float) period);

        System.out.println("expectedAPC = " + expectedAPC);

        expectedAPC = adjustExpectedAPCForAvailableCPUs(expectedAPC);

        DockerRunOptions opts = Common.newOpts(imageName)

            .addDockerOpts("--cpu-period=" + period)

            .addDockerOpts("--cpu-quota=" + quota);

        Common.run(opts)

            .shouldMatch("CPU Period is.*" + period)

            .shouldMatch("CPU Quota is.*" + quota)

            .shouldMatch("active_processor_count.*" + expectedAPC);

    }

    // Test correctess of automatically selected active processor cound

    private static void testAPCCombo(String cpuset, int quota, int period, int shares,

                                     boolean usePreferContainerQuotaForCPUCount,

                                     int expectedAPC) throws Exception {

        Common.logNewTestCase("test APC Combo");

        System.out.println("cpuset = " + cpuset);

        System.out.println("quota = " + quota);

        System.out.println("period = " + period);

        System.out.println("shares = " + period);

        System.out.println("usePreferContainerQuotaForCPUCount = " + usePreferContainerQuotaForCPUCount);

        System.out.println("expectedAPC = " + expectedAPC);

        expectedAPC = adjustExpectedAPCForAvailableCPUs(expectedAPC);

        DockerRunOptions opts = Common.newOpts(imageName)

            .addDockerOpts("--cpuset-cpus", "" + cpuset)

            .addDockerOpts("--cpu-period=" + period)

            .addDockerOpts("--cpu-quota=" + quota)

            .addDockerOpts("--cpu-shares=" + shares);

        if (!usePreferContainerQuotaForCPUCount) opts.addJavaOpts("-XX:-PreferContainerQuotaForCPUCount");

        Common.run(opts)

            .shouldMatch("active_processor_count.*" + expectedAPC);

    }

    private static void testCpuShares(int shares, int expectedAPC) throws Exception {

        Common.logNewTestCase("test cpu shares, shares = " + shares);

        System.out.println("expectedAPC = " + expectedAPC);

        expectedAPC = adjustExpectedAPCForAvailableCPUs(expectedAPC);

        DockerRunOptions opts = Common.newOpts(imageName)

            .addDockerOpts("--cpu-shares=" + shares);

        Common.run(opts)

            .shouldMatch("CPU Shares is.*" + shares)

            .shouldMatch("active_processor_count.*" + expectedAPC);

    }

}