cc-metric-collector/collectors/perfEventMetric.md

perf_event collector

This collector uses directly the perf_event_open system call to measure events. There is no name to event translation, the configuration has to be as low-level as required by the system call. It allows to aggregate the measurements to topological entities like socket or the whole node.

Configuration

{
    "events" : [
        {
            "name" : "instructions",
            "unit" : "uncore_imc_0",
            "config": "0x01",
            "scale_file" : "/sys/devices/<unit>/events/<event>.scale",
            "per_hwthread": true,
            "per_socket": true,
            "exclude_kernel": true,
            "exclude_hypervisor": true,
            "tags": {
                "tags": "just_for_the_event"
            },
            "meta": {
                "meta_info": "just_for_the_event"
            },
            "config1": "0x00",
            "config2": "0x00",
        }
    ]
}

• events: List of events to measure
• name: Name for the metric
• unit: Unit of the event or cpu if not given. The unit type ID is resolved by reading the file /sys/devices/<unit>/type. The unit type ID is then written to the perf_event_attr struct member type.
• config: Hex value written to the perf_event_attr struct member config.
• config1: Hex value written to the perf_event_attr struct member config1 (optional).
• config2: Hex value written to the perf_event_attr struct member config1 (optional).
• scale_file: If a measurement requires scaling, like the power unit aka RAPL, it is provided by the kernel in a .scale file at /sys/devices/<unit>/events/<event>.scale.
• exclude_kernel: Exclude the kernel from measurements (default: true). It sets the perf_event_attr struct member exclude_kernel.
• exclude_hypervisor: Exclude the hypervisors from measurements (default: true). It sets the perf_event_attr struct member exclude_hypervisor.
• per_hwthread: Generate metrics per hardware thread (default: false)
• per_socket: Generate metrics per hardware thread (default: false)
• tags: Tags just for the event.
• meta: Meta information just for the event, often a unit