{
    select: {
        free_bytes: "INSPECT:memory_monitor.cmx:root/values:free_bytes",
        total_bytes: "INSPECT:memory_monitor.cmx:root/values:total_bytes",
        kmem_free_bytes: "INSPECT:memory_monitor.cmx:root/values:free_heap_bytes",
        kmem_total_bytes: "INSPECT:memory_monitor.cmx:root/values:kmem_total_bytes",
    },
    eval: {
        free_ratio: "free_bytes / total_bytes",
        used_ratio: "(total_bytes - free_bytes) / total_bytes",
        megabytes: "1024 * 1024",

        // 150MiB free is "CRITICAL"
        critical_limit: "150 * megabytes",

        // 50MiB free is "OOM"
        oom_limit: "50 * megabytes",
    },
    act: {
        free_memory_mb: {
            type: "Gauge",
            value: "free_bytes // megabytes",
        },
        memory_usage: {
            type: "Gauge",
            value: "used_ratio",
            format: "percentage",
        },
        critical_memory: {
            type: "Warning",
            trigger: "free_bytes < critical_limit",
            print: "Memory usage is CRITICAL",
        },
        oom: {
            type: "Warning",
            trigger: "free_bytes < oom_limit",
            print: "The system is Out of Memory!",
        },
    },
    test: {
        critical: {
            yes: [
                "critical_memory",
            ],
            no: [
                "oom",
            ],
            values: {
                free_bytes: 100000000,
            },
        },
        oom: {
            yes: [
                "critical_memory",
                "oom",
            ],
            values: {
                free_bytes: 100000,
            },
        },
        ok: {
            no: [
                "critical_memory",
                "oom",
            ],
            values: {
                free_bytes: 1000000000000,
            },
        },
    },
}