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MaharachaMaharacha
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collector/diskstats: add device-mapper backing device info metric
1 parent 4d32635 commit 48e8ac6

3 files changed

Lines changed: 89 additions & 0 deletions

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‎collector/diskstats_linux.go‎

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Original file line numberDiff line numberDiff line change
@@ -20,6 +20,7 @@ import (
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"fmt"
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"log/slog"
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"os"
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"sort"
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"strconv"
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"strings"
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@@ -74,6 +75,7 @@ type diskstatsCollector struct {
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descs []typedDesc
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filesystemInfoDesc typedDesc
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deviceMapperInfoDesc typedDesc
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deviceMapperBackingDesc typedDesc
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ataDescs map[string]typedDesc
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logger *slog.Logger
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getUdevDeviceProperties func(uint32, uint32) (udevInfo, error)
@@ -224,6 +226,13 @@ func NewDiskstatsCollector(logger *slog.Logger) (Collector, error) {
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nil,
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), valueType: prometheus.GaugeValue,
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},
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deviceMapperBackingDesc: typedDesc{
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desc: prometheus.NewDesc(prometheus.BuildFQName(namespace, diskSubsystem, "device_mapper_backing_device_info"),
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"Info about the underlying block devices of a device mapper device.",
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[]string{"device", "backing_device"},
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nil,
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), valueType: prometheus.GaugeValue,
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},
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ataDescs: map[string]typedDesc{
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udevIDATAWriteCache: {
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desc: prometheus.NewDesc(prometheus.BuildFQName(namespace, diskSubsystem, "ata_write_cache"),
@@ -351,6 +360,7 @@ func (c *diskstatsCollector) Update(ch chan<- prometheus.Metric) error {
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info[udevDMLVName],
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info[udevDMLVLayer],
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)
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c.updateDeviceMapperBackingDevices(ch, dev)
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}
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if ata := info[udevIDATA]; ata != "" {
@@ -372,6 +382,23 @@ func (c *diskstatsCollector) Update(ch chan<- prometheus.Metric) error {
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return nil
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}
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func (c *diskstatsCollector) updateDeviceMapperBackingDevices(ch chan<- prometheus.Metric, dev string) {
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underlying, err := c.fs.SysBlockDeviceUnderlyingDevices(dev)
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if err != nil {
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if !os.IsNotExist(err) {
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c.logger.Debug("Failed to get device mapper backing devices", "device", dev, "err", err)
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}
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return
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}
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sort.Strings(underlying.DeviceNames)
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for _, backingDevice := range underlying.DeviceNames {
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ch <- c.deviceMapperBackingDesc.mustNewConstMetric(1.0, dev,
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backingDevice,
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)
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}
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}
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func getUdevDeviceProperties(major, minor uint32) (udevInfo, error) {
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filename := udevDataFilePath(fmt.Sprintf("b%d:%d", major, minor))
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‎collector/diskstats_linux_test.go‎

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Original file line numberDiff line numberDiff line change
@@ -68,6 +68,14 @@ node_disk_ata_write_cache{device="sdc"} 1
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node_disk_ata_write_cache_enabled{device="sda"} 0
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node_disk_ata_write_cache_enabled{device="sdb"} 1
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node_disk_ata_write_cache_enabled{device="sdc"} 0
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# HELP node_disk_device_mapper_backing_device_info Info about the underlying block devices of a device mapper device.
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# TYPE node_disk_device_mapper_backing_device_info gauge
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node_disk_device_mapper_backing_device_info{backing_device="nvme0n1p3",device="dm-0"} 1
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node_disk_device_mapper_backing_device_info{backing_device="dm-0",device="dm-1"} 1
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node_disk_device_mapper_backing_device_info{backing_device="dm-0",device="dm-2"} 1
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node_disk_device_mapper_backing_device_info{backing_device="dm-0",device="dm-3"} 1
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node_disk_device_mapper_backing_device_info{backing_device="dm-0",device="dm-4"} 1
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node_disk_device_mapper_backing_device_info{backing_device="dm-0",device="dm-5"} 1
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# HELP node_disk_device_mapper_info Info about disk device mapper.
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# TYPE node_disk_device_mapper_info gauge
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node_disk_device_mapper_info{device="dm-0",lv_layer="",lv_name="",name="nvme0n1_crypt",uuid="CRYPT-LUKS2-jolaulot80fy9zsiobkxyxo7y2dqeho2-nvme0n1_crypt",vg_name=""} 1

‎collector/fixtures/sys.ttar‎

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@@ -5,6 +5,60 @@ Mode: 755
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Directory: sys/block
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-0
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-0/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-0/slaves/nvme0n1p3
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SymlinkTo: ../nvme0n1p3
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-1
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-1/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-1/slaves/dm-0
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SymlinkTo: ../dm-0
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-2
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-2/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-2/slaves/dm-0
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SymlinkTo: ../dm-0
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-3
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-3/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-3/slaves/dm-0
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SymlinkTo: ../dm-0
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-4
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-4/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-4/slaves/dm-0
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SymlinkTo: ../dm-0
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-5
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/dm-5/slaves
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Path: sys/block/dm-5/slaves/dm-0
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SymlinkTo: ../dm-0
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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Directory: sys/block/md0
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Mode: 755
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# ttar - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

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