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preface

This section describes the code for the ServerController part of the server monitoring module in ruoyi-Vue’s Ruoyi-admin module. This interface is mainly used to show the server

code

   public AjaxResult getInfo(a) throws Exception {
        Server server = new Server();
        server.copyTo();
        return AjaxResult.success(server);
    }
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All the code is in the copyTo() method, which calls Oshi-core

            <dependency>
                <groupId>com.github.oshi</groupId>
                <artifactId>oshi-core</artifactId>
                <version>${oshi.version}</version>
            </dependency>
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Oshi-core is a third-party JAR package for obtaining hardware and system information. Based on JNA

Get CPU information

        SystemInfo si = new SystemInfo();
        HardwareAbstractionLayer hal = si.getHardware();
        setCpuInfo(hal.getProcessor());

    private void setCpuInfo(CentralProcessor processor)
    {
        / / CPU information
        long[] prevTicks = processor.getSystemCpuLoadTicks();
        Util.sleep(OSHI_WAIT_SECOND);
        long[] ticks = processor.getSystemCpuLoadTicks();
        long nice = ticks[TickType.NICE.getIndex()] - prevTicks[TickType.NICE.getIndex()];
        long irq = ticks[TickType.IRQ.getIndex()] - prevTicks[TickType.IRQ.getIndex()];
        long softirq = ticks[TickType.SOFTIRQ.getIndex()] - prevTicks[TickType.SOFTIRQ.getIndex()];
        long steal = ticks[TickType.STEAL.getIndex()] - prevTicks[TickType.STEAL.getIndex()];
        long cSys = ticks[TickType.SYSTEM.getIndex()] - prevTicks[TickType.SYSTEM.getIndex()];
        long user = ticks[TickType.USER.getIndex()] - prevTicks[TickType.USER.getIndex()];
        long iowait = ticks[TickType.IOWAIT.getIndex()] - prevTicks[TickType.IOWAIT.getIndex()];
        long idle = ticks[TickType.IDLE.getIndex()] - prevTicks[TickType.IDLE.getIndex()];
        long totalCpu = user + nice + cSys + idle + iowait + irq + softirq + steal;
        cpu.setCpuNum(processor.getLogicalProcessorCount());
        cpu.setTotal(totalCpu);
        cpu.setSys(cSys);
        cpu.setUsed(user);
        cpu.setWait(iowait);
        cpu.setFree(idle);
    }
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IDLE

The time when the CPU is idle and the system has no outstanding disk I/O requests

IOWAIT

The amount of time the CPU is idle and the system has an outstanding disk I/O request, unavailable on Windows and MacOS is 0.

IRQ (Hardware Interrupts)

The CPU time used to service hardware interrupts, which is not available in MacOS, is always 0

NICE

CPU utilization that occurs when executing at the user level with nice priority

Nice is a static priority value. It is unique to Unix-like systems and will not be changed by the kernel until it is reset.

SOFTIRQ

The CPU time used to service software outages

STEAL

Time allocated by the operating system to other users in the system

SYSTEM

System-level CPU utilization

USER

User-level run-time CPU utilization

When using the Linux Top command we can see the above data, the site directly displayed on the page to facilitate the monitoring of server data.

Setting Server Information

    private void setSysInfo(a) {

        Properties props = System.getProperties();

        sys.setComputerName(IpUtils.getHostName());

        sys.setComputerIp(IpUtils.getHostIp());

        sys.setOsName(props.getProperty("os.name"));

        sys.setOsArch(props.getProperty("os.arch"));

        sys.setUserDir(props.getProperty("user.dir"));

    }

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Obtain Java VM information

   /** * Set the Java virtual machine */

    private void setJvmInfo(a) throws UnknownHostException

    {

        Properties props = System.getProperties();

        jvm.setTotal(Runtime.getRuntime().totalMemory());

        jvm.setMax(Runtime.getRuntime().maxMemory());

        jvm.setFree(Runtime.getRuntime().freeMemory());

        jvm.setVersion(props.getProperty("java.version"));

        jvm.setHome(props.getProperty("java.home"));

    }

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