Add hostname label to exporter metrics

pkg/collector/cli.go

@@ -36,6 +36,9 @@ var BatchJobExporterApp = *kingpin.New(
 	"Prometheus Exporter to export batch job metrics.",
 )
 
+// Empty hostname flag (Used only for testing)
+var emptyHostnameLabel *bool
+
 // Create a new BatchJobExporter struct
 func NewBatchJobExporter() (*BatchJobExporter, error) {
 	return &BatchJobExporter{
@@ -91,6 +94,12 @@ func (b *BatchJobExporter) Main() {
 		toolkitFlags = kingpinflag.AddFlags(&b.App, ":9010")
 	)
 
+	// This is hidden flag only used for e2e testing
+	emptyHostnameLabel = b.App.Flag(
+		"collector.empty.hostname.label",
+		"Use empty hostname in labels. Only for testing. (default is disabled)",
+	).Hidden().Default("false").Bool()
+
 	promlogConfig := &promlog.Config{}
 	flag.AddFlags(&b.App, promlogConfig)
 	b.App.Version(version.Print(b.appName))

pkg/collector/fixtures/e2e-test-cgroupsv1-output.txt

@@ -1,52 +1,52 @@
 # HELP batchjob_cpu_system_seconds Cumulative CPU system seconds
 # TYPE batchjob_cpu_system_seconds gauge
-batchjob_cpu_system_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0.45
+batchjob_cpu_system_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0.45
 # HELP batchjob_cpu_total_seconds Cumulative CPU total seconds
 # TYPE batchjob_cpu_total_seconds gauge
-batchjob_cpu_total_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 1.012410966
+batchjob_cpu_total_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 1.012410966
 # HELP batchjob_cpu_user_seconds Cumulative CPU user seconds
 # TYPE batchjob_cpu_user_seconds gauge
-batchjob_cpu_user_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0.39
+batchjob_cpu_user_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0.39
 # HELP batchjob_cpus Number of CPUs
 # TYPE batchjob_cpus gauge
-batchjob_cpus{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_cpus{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_exporter_build_info A metric with a constant '1' value labeled by version, revision, branch, goversion from which batchjob_exporter was built, and the goos and goarch for the build.
 # TYPE batchjob_exporter_build_info gauge
 # HELP batchjob_ipmi_dcmi_watts_total Current Power consumption in watts
 # TYPE batchjob_ipmi_dcmi_watts_total counter
-batchjob_ipmi_dcmi_watts_total 332
+batchjob_ipmi_dcmi_watts_total{hostname=""} 332
 # HELP batchjob_memory_cache_bytes Memory cache used in bytes
 # TYPE batchjob_memory_cache_bytes gauge
-batchjob_memory_cache_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2.1086208e+07
+batchjob_memory_cache_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2.1086208e+07
 # HELP batchjob_memory_fail_count Memory fail count
 # TYPE batchjob_memory_fail_count gauge
-batchjob_memory_fail_count{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memory_fail_count{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_memory_rss_bytes Memory RSS used in bytes
 # TYPE batchjob_memory_rss_bytes gauge
-batchjob_memory_rss_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 1.0407936e+07
+batchjob_memory_rss_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 1.0407936e+07
 # HELP batchjob_memory_total_bytes Memory total in bytes
 # TYPE batchjob_memory_total_bytes gauge
-batchjob_memory_total_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2.01362030592e+11
+batchjob_memory_total_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2.01362030592e+11
 # HELP batchjob_memory_used_bytes Memory used in bytes
 # TYPE batchjob_memory_used_bytes gauge
-batchjob_memory_used_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.0194048e+07
+batchjob_memory_used_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.0194048e+07
 # HELP batchjob_memsw_fail_count Swap fail count
 # TYPE batchjob_memsw_fail_count gauge
-batchjob_memsw_fail_count{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memsw_fail_count{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_memsw_total_bytes Swap total in bytes
 # TYPE batchjob_memsw_total_bytes gauge
-batchjob_memsw_total_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 9.223372036854772e+18
+batchjob_memsw_total_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 9.223372036854772e+18
 # HELP batchjob_memsw_used_bytes Swap used in bytes
 # TYPE batchjob_memsw_used_bytes gauge
-batchjob_memsw_used_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.032512e+07
+batchjob_memsw_used_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.032512e+07
 # HELP batchjob_nvidia_gpu_jobid Batch Job ID of current nVIDIA GPU
 # TYPE batchjob_nvidia_gpu_jobid gauge
-batchjob_nvidia_gpu_jobid{uuid="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3"} 11000
-batchjob_nvidia_gpu_jobid{uuid="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e"} 10000
+batchjob_nvidia_gpu_jobid{UUID="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3",hostname="",uuid="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3"} 11000
+batchjob_nvidia_gpu_jobid{UUID="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e",hostname="",uuid="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e"} 10000
 # HELP batchjob_rapl_package_joules_total Current RAPL package value in joules
 # TYPE batchjob_rapl_package_joules_total counter
-batchjob_rapl_package_joules_total{index="0",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:0"} 258218.293244
-batchjob_rapl_package_joules_total{index="1",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:1"} 130570.505826
+batchjob_rapl_package_joules_total{hostname="",index="0",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:0"} 258218.293244
+batchjob_rapl_package_joules_total{hostname="",index="1",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:1"} 130570.505826
 # HELP batchjob_scrape_collector_duration_seconds batchjob_exporter: Duration of a collector scrape.
 # TYPE batchjob_scrape_collector_duration_seconds gauge
 # HELP batchjob_scrape_collector_success batchjob_exporter: Whether a collector succeeded.

pkg/collector/fixtures/e2e-test-cgroupsv2-output.txt

@@ -1,52 +1,52 @@
 # HELP batchjob_cpu_system_seconds Cumulative CPU system seconds
 # TYPE batchjob_cpu_system_seconds gauge
-batchjob_cpu_system_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 115.777502
+batchjob_cpu_system_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 115.777502
 # HELP batchjob_cpu_total_seconds Cumulative CPU total seconds
 # TYPE batchjob_cpu_total_seconds gauge
-batchjob_cpu_total_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 60491.070351
+batchjob_cpu_total_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 60491.070351
 # HELP batchjob_cpu_user_seconds Cumulative CPU user seconds
 # TYPE batchjob_cpu_user_seconds gauge
-batchjob_cpu_user_seconds{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 60375.292848
+batchjob_cpu_user_seconds{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 60375.292848
 # HELP batchjob_cpus Number of CPUs
 # TYPE batchjob_cpus gauge
-batchjob_cpus{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2
+batchjob_cpus{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 2
 # HELP batchjob_exporter_build_info A metric with a constant '1' value labeled by version, revision, branch, goversion from which batchjob_exporter was built, and the goos and goarch for the build.
 # TYPE batchjob_exporter_build_info gauge
 # HELP batchjob_ipmi_dcmi_watts_total Current Power consumption in watts
 # TYPE batchjob_ipmi_dcmi_watts_total counter
-batchjob_ipmi_dcmi_watts_total 332
+batchjob_ipmi_dcmi_watts_total{hostname=""} 332
 # HELP batchjob_memory_cache_bytes Memory cache used in bytes
 # TYPE batchjob_memory_cache_bytes gauge
-batchjob_memory_cache_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memory_cache_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_memory_fail_count Memory fail count
 # TYPE batchjob_memory_fail_count gauge
-batchjob_memory_fail_count{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memory_fail_count{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_memory_rss_bytes Memory RSS used in bytes
 # TYPE batchjob_memory_rss_bytes gauge
-batchjob_memory_rss_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.098592768e+09
+batchjob_memory_rss_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.098592768e+09
 # HELP batchjob_memory_total_bytes Memory total in bytes
 # TYPE batchjob_memory_total_bytes gauge
-batchjob_memory_total_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.294967296e+09
+batchjob_memory_total_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.294967296e+09
 # HELP batchjob_memory_used_bytes Memory used in bytes
 # TYPE batchjob_memory_used_bytes gauge
-batchjob_memory_used_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.111491072e+09
+batchjob_memory_used_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 4.111491072e+09
 # HELP batchjob_memsw_fail_count Swap fail count
 # TYPE batchjob_memsw_fail_count gauge
-batchjob_memsw_fail_count{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memsw_fail_count{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_memsw_total_bytes Swap total in bytes
 # TYPE batchjob_memsw_total_bytes gauge
-batchjob_memsw_total_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} -1
+batchjob_memsw_total_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} -1
 # HELP batchjob_memsw_used_bytes Swap used in bytes
 # TYPE batchjob_memsw_used_bytes gauge
-batchjob_memsw_used_bytes{batch="slurm",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
+batchjob_memsw_used_bytes{batch="slurm",hostname="",jobaccount="testacc",jobid="1009248",jobuuid="ac28caf5-ce6c-35f6-73fb-47d9d43f7780",step="",task=""} 0
 # HELP batchjob_nvidia_gpu_jobid Batch Job ID of current nVIDIA GPU
 # TYPE batchjob_nvidia_gpu_jobid gauge
-batchjob_nvidia_gpu_jobid{uuid="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3"} 11000
-batchjob_nvidia_gpu_jobid{uuid="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e"} 10000
+batchjob_nvidia_gpu_jobid{UUID="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3",hostname="",uuid="GPU-61a65011-6571-a6d2-5ab8-66cbb6f7f9c3"} 11000
+batchjob_nvidia_gpu_jobid{UUID="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e",hostname="",uuid="GPU-f124aa59-d406-d45b-9481-8fcd694e6c9e"} 10000
 # HELP batchjob_rapl_package_joules_total Current RAPL package value in joules
 # TYPE batchjob_rapl_package_joules_total counter
-batchjob_rapl_package_joules_total{index="0",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:0"} 258218.293244
-batchjob_rapl_package_joules_total{index="1",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:1"} 130570.505826
+batchjob_rapl_package_joules_total{hostname="",index="0",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:0"} 258218.293244
+batchjob_rapl_package_joules_total{hostname="",index="1",path="pkg/collector/fixtures/sys/class/powercap/intel-rapl:1"} 130570.505826
 # HELP batchjob_scrape_collector_duration_seconds batchjob_exporter: Duration of a collector scrape.
 # TYPE batchjob_scrape_collector_duration_seconds gauge
 # HELP batchjob_scrape_collector_success batchjob_exporter: Whether a collector succeeded.

pkg/collector/ipmi.go

@@ -8,6 +8,7 @@ package collector
 
 import (
 	"fmt"
+	"os"
 	"regexp"
 	"strconv"
 	"strings"
@@ -22,6 +23,7 @@ const ipmiCollectorSubsystem = "ipmi_dcmi"
 
 type impiCollector struct {
 	logger          log.Logger
+	hostname        string
 	execMode        string
 	wattsMetricDesc *prometheus.Desc
 }
@@ -45,14 +47,23 @@ func init() {
 
 // NewIPMICollector returns a new Collector exposing IMPI DCMI power metrics.
 func NewIPMICollector(logger log.Logger) (Collector, error) {
+	var execMode string
+	var hostname string
+	var err error
+
+	// Get hostname
+	if !*emptyHostnameLabel {
+		hostname, err = os.Hostname()
+		if err != nil {
+			level.Error(logger).Log("msg", "Failed to get hostname", "err", err)
+		}
+	}
 
 	wattsMetricDesc := prometheus.NewDesc(
 		prometheus.BuildFQName(Namespace, ipmiCollectorSubsystem, "watts_total"),
-		"Current Power consumption in watts", []string{}, nil,
+		"Current Power consumption in watts", []string{"hostname"}, nil,
 	)
 
-	var execMode string
-
 	// Split command
 	cmdSlice := strings.Split(*ipmiDcmiCmd, " ")
 
@@ -81,6 +92,7 @@ func NewIPMICollector(logger log.Logger) (Collector, error) {
 outside:
 	collector := impiCollector{
 		logger:          logger,
+		hostname:        hostname,
 		execMode:        execMode,
 		wattsMetricDesc: wattsMetricDesc,
 	}
@@ -134,7 +146,7 @@ func (c *impiCollector) Update(ch chan<- prometheus.Metric) error {
 
 	// Returned value negative == Power Measurement is not avail
 	if currentPowerConsumption > -1 {
-		ch <- prometheus.MustNewConstMetric(c.wattsMetricDesc, prometheus.CounterValue, float64(currentPowerConsumption))
+		ch <- prometheus.MustNewConstMetric(c.wattsMetricDesc, prometheus.CounterValue, float64(currentPowerConsumption), c.hostname)
 	}
 	return nil
 }

pkg/collector/nvidia_gpus.go

@@ -42,6 +42,7 @@ type Device struct {
 type nvidiaGpuJobMapCollector struct {
 	devices       []Device
 	logger        log.Logger
+	hostname      string
 	gpuJobMapDesc *prometheus.Desc
 }
 
@@ -116,16 +117,28 @@ func getAllDevices(logger log.Logger) ([]Device, error) {
 
 // NewNvidiaGpuJobMapCollector returns a new Collector exposing batch jobs to nVIDIA GPU ordinals mapping.
 func NewNvidiaGpuJobMapCollector(logger log.Logger) (Collector, error) {
+	var hostname string
+	var err error
+
+	// Get hostname
+	if !*emptyHostnameLabel {
+		hostname, err = os.Hostname()
+		if err != nil {
+			level.Error(logger).Log("msg", "Failed to get hostname", "err", err)
+		}
+	}
+
 	allDevices, _ := getAllDevices(logger)
 	gpuJobMapDesc := prometheus.NewDesc(
 		prometheus.BuildFQName(Namespace, nvidiaGpuJobMapCollectorSubsystem, "jobid"),
 		"Batch Job ID of current nVIDIA GPU",
-		[]string{"uuid"}, nil,
+		[]string{"hostname", "uuid", "UUID"}, nil,
 	)
 
 	collector := nvidiaGpuJobMapCollector{
 		devices:       allDevices,
 		logger:        logger,
+		hostname:      hostname,
 		gpuJobMapDesc: gpuJobMapDesc,
 	}
 	return &collector, nil
@@ -135,7 +148,7 @@ func NewNvidiaGpuJobMapCollector(logger log.Logger) (Collector, error) {
 func (c *nvidiaGpuJobMapCollector) Update(ch chan<- prometheus.Metric) error {
 	gpuJobMapper, _ := c.getJobId()
 	for _, dev := range c.devices {
-		ch <- prometheus.MustNewConstMetric(c.gpuJobMapDesc, prometheus.GaugeValue, gpuJobMapper[dev.uuid], dev.uuid)
+		ch <- prometheus.MustNewConstMetric(c.gpuJobMapDesc, prometheus.GaugeValue, gpuJobMapper[dev.uuid], c.hostname, dev.uuid, dev.uuid)
 	}
 	return nil
 }

pkg/collector/rapl.go

@@ -20,9 +20,9 @@ import (
 const raplCollectorSubsystem = "rapl"
 
 type raplCollector struct {
-	fs     sysfs.FS
-	logger log.Logger
-
+	fs               sysfs.FS
+	logger           log.Logger
+	hostname         string
 	joulesMetricDesc *prometheus.Desc
 }
 
@@ -39,21 +39,32 @@ var (
 
 // NewRaplCollector returns a new Collector exposing RAPL metrics.
 func NewRaplCollector(logger log.Logger) (Collector, error) {
-	fs, err := sysfs.NewFS(*sysPath)
+	var hostname string
+	var err error
 
+	// Get hostname
+	if !*emptyHostnameLabel {
+		hostname, err = os.Hostname()
+		if err != nil {
+			level.Error(logger).Log("msg", "Failed to get hostname", "err", err)
+		}
+	}
+
+	fs, err := sysfs.NewFS(*sysPath)
 	if err != nil {
 		return nil, err
 	}
 
 	joulesMetricDesc := prometheus.NewDesc(
 		prometheus.BuildFQName(Namespace, raplCollectorSubsystem, "joules_total"),
 		"Current RAPL value in joules",
-		[]string{"index", "path", "rapl_zone"}, nil,
+		[]string{"hostname", "index", "path", "rapl_zone"}, nil,
 	)
 
 	collector := raplCollector{
 		fs:               fs,
 		logger:           logger,
+		hostname:         hostname,
 		joulesMetricDesc: joulesMetricDesc,
 	}
 	return &collector, nil
@@ -107,25 +118,25 @@ func (c *raplCollector) joulesMetric(z sysfs.RaplZone, v float64) prometheus.Met
 			fmt.Sprintf("%s_joules_total", SanitizeMetricName(z.Name)),
 		),
 		fmt.Sprintf("Current RAPL %s value in joules", z.Name),
-		[]string{"index", "path"}, nil,
+		[]string{"hostname", "index", "path"}, nil,
 	)
-
 	return prometheus.MustNewConstMetric(
 		descriptor,
 		prometheus.CounterValue,
 		v,
+		c.hostname,
 		index,
 		z.Path,
 	)
 }
 
 func (c *raplCollector) joulesMetricWithZoneLabel(z sysfs.RaplZone, v float64) prometheus.Metric {
 	index := strconv.Itoa(z.Index)
-
 	return prometheus.MustNewConstMetric(
 		c.joulesMetricDesc,
 		prometheus.CounterValue,
 		v,
+		c.hostname,
 		index,
 		z.Path,
 		z.Name,