Metrics specifications

This article explains the metrics displayed in the host details screen as well as in the service details screen.

System metrics

Metrics automatically collected / posted by installing / launching mackerel-agent.

Linux

There are six types of graphs which will be displayed: loadavg, cpu, memory, disk, interface, and filesystem. The following are the metric values which will be graphed by each.

  • loadavg(line graph)
    • loadavg1
    • loadavg5
    • loadavg15
  • cpu(stacked graph)
    • cpu.user.percentage
    • cpu.iowait.percentage
    • cpu.system.percentage
    • cpu.idle.percentage
    • cpu.nice.percentage
    • cpu.irq.percentage
    • cpu.softirq.percentage
    • cpu.steal.percentage
    • cpu.guest.percentage
  • memory(stacked graph. memory.total, swap_total, swap_used, and swap_cached are line graphs)
    • Kernel 3.14 or later for Linux
      • memory.used
      • memory.available
      • memory.total
      • memory.swap_used
      • memory.swap_cached
      • memory.swap_total
    • Other Linux
      • memory.free
      • memory.buffers
      • memory.cached
      • memory.used
      • memory.total
      • memory.swap_used
      • memory.swap_cached
      • memory.swap_total
  • disk（line graph）
    • disk.*.reads.delta
    • disk.*.writes.delta
  • interface（line graph）
    • interface.*.rxBytes.delta (受信バイト数)
    • interface.*.txBytes.delta (送信バイト数)
  • filesystem（line graph）
    • filesystem.*.size
    • filesystem.*.used

The sources for each of the above metrics when using mackerel-agent are as follows.

  • loadavg
    • Obtained by parsing the contents of /proc/loadavg
  • cpu
    • Obtained by parsing the contents of /proc/stat
  • memory
    • Obtained by parsing the contents of /proc/meminfo
  • disk
    • Obtained by parsing the contents of /proc/diskstats
  • interface
    • Obtained by parsing the contents of /proc/net/dev
  • filesystem
    • Obtained by parsing the execution results of the df command

You can take a look at the mackerel-agent source code published in the link below.

github.com

Windows

There are six types of graphs which will be displayed: processor queue length, cpu, memory, disk, interface, and filesystem. The following are the metric values which will be graphed by each.

  • processor queue length（line graph）
    • processor_queue_length
  • cpu（stacked graph）
    • cpu.user.percentage
    • cpu.system.percentage
    • cpu.idle.percentage
  • memory（stacked graph. memory.total, pagefile_free, and pagefile_total are line graphs）
    • memory.free
    • memory.used
    • memory.total
    • memory.pagefile_free
    • memory.pagefile_total
  • disk(line graph)
    • disk.*.reads.delta
    • disk.*.writes.delta
  • interface(line graph)
    • interface.*.rxBytes.delta　(the number of bytes received)
    • interface.*.txBytes.delta　(the number of bytes sent)
  • filesystem(line graph)
    • filesystem.*.size
    • filesystem.*.used

The sources for each of the above metrics when using mackerel-agent are as follows.

  • processor queue length
    • Information is obtained with the Windows Performance Data Helper API
  • cpu
    • Information is obtained with the Windows Performance Data Helper API
  • memory
    • Obtained from the results of the Win32 API GlobalMemoryStatusEx
  • disk
    • Information is obtained from the Win32_PerfFormattedData_PerfDisk_LogicalDisk class using WMI
  • interface
    • Information is obtained with the Windows Performance Data Helper API
  • filesystem
    • Obtained and calculated from the results of the following Win32 API functions
      • GetLogicalDriveStringsW
      • QueryDosDeviceW
      • GetVolumeInformationW
      • GetDiskFreeSpaceExW

You can take a look at the mackerel-agent source code published in the link below.

github.com

User-defined metrics (Custom metrics)

  • custom.foo(.bar)*.*
    • Metrics which have the same name up to the last dot in the name will be collected together and displayed in one graph.

Custom metrics sent from mackerel-agent are attached with the prefix custom. (from version 0.6.1). We recommend adding custom. even when using the API directly because system metrics may now be added with the mackerel-agent update. See also Posting user-defined custom metrics.