Lustre filesystem plugin (http://lustre.org/)

The configuration allows users to override the /proc/ files
scanned for data, since that has been known to change with lustre
versions.

plugins/lustre2/lustre2.go

@@ -0,0 +1,235 @@
+// +build linux
+/*
+Lustre 2.x telegraf plugin
+
+Lustre (http://lustre.org/) is an open-source, parallel file system
+for HPC environments. It stores statistics about its activity in
+/proc
+
+*/
+package lustre2
+
+import (
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"github.com/influxdb/telegraf/plugins"
+	common "github.com/influxdb/telegraf/plugins/system/ps/common"
+)
+
+// Lustre proc files can change between versions, so we want to future-proof
+// by letting people choose what to look at.
+type Lustre2 struct {
+	Ost_procfiles []string
+	Mds_procfiles []string
+}
+
+var sampleConfig = `
+# An array of /proc globs to search for Lustre stats
+# If not specified, the default will work on Lustre 2.5.x
+#
+# ost_procfiles = ["/proc/fs/lustre/obdfilter/*/stats", "/proc/fs/lustre/osd-ldiskfs/*/stats"]
+# mds_procfiles = ["/proc/fs/lustre/mdt/*/md_stats"]`
+
+/* The wanted fields would be a []string if not for the
+lines that start with read_bytes/write_bytes and contain
+   both the byte count and the function call count
+*/
+type mapping struct {
+	inProc   string // What to look for at the start of a line in /proc/fs/lustre/*
+	field    uint32 // which field to extract from that line
+	reportAs string // What measurement name to use
+	tag      string // Additional tag to add for this metric
+}
+
+var wanted_ost_fields = []*mapping{
+	{
+		inProc:   "write_bytes",
+		field:    6,
+		reportAs: "write_bytes",
+	},
+	{ // line starts with 'write_bytes', but value write_calls is in second column
+		inProc:   "write_bytes",
+		field:    1,
+		reportAs: "write_calls",
+	},
+	{
+		inProc:   "read_bytes",
+		field:    6,
+		reportAs: "read_bytes",
+	},
+	{ // line starts with 'read_bytes', but value read_calls is in second column
+		inProc:   "read_bytes",
+		field:    1,
+		reportAs: "read_calls",
+	},
+	{
+		inProc: "cache_hit",
+	},
+	{
+		inProc: "cache_miss",
+	},
+	{
+		inProc: "cache_access",
+	},
+}
+
+var wanted_mds_fields = []*mapping{
+	{
+		inProc: "open",
+	},
+	{
+		inProc: "close",
+	},
+	{
+		inProc: "mknod",
+	},
+	{
+		inProc: "link",
+	},
+	{
+		inProc: "unlink",
+	},
+	{
+		inProc: "mkdir",
+	},
+	{
+		inProc: "rmdir",
+	},
+	{
+		inProc: "rename",
+	},
+	{
+		inProc: "getattr",
+	},
+	{
+		inProc: "setattr",
+	},
+	{
+		inProc: "getxattr",
+	},
+	{
+		inProc: "setxattr",
+	},
+	{
+		inProc: "statfs",
+	},
+	{
+		inProc: "sync",
+	},
+	{
+		inProc: "samedir_rename",
+	},
+	{
+		inProc: "crossdir_rename",
+	},
+}
+
+func (l *Lustre2) GetLustreProcStats(fileglob string, wanted_fields []*mapping, acc plugins.Accumulator) error {
+	files, err := filepath.Glob(fileglob)
+	if err != nil {
+		return err
+	}
+
+	for _, file := range files {
+		/* Turn /proc/fs/lustre/obdfilter/<ost_name>/stats and similar
+		 * into just the object store target name
+		 * Assumpion: the target name is always second to last,
+		 * which is true in Lustre 2.1->2.5
+		 */
+		path := strings.Split(file, "/")
+		name := path[len(path)-2]
+		tags := map[string]string{
+			"name": name,
+		}
+
+		lines, err := common.ReadLines(file)
+		if err != nil {
+			return err
+		}
+
+		for _, line := range lines {
+			fields := strings.Fields(line)
+
+			for _, wanted := range wanted_fields {
+				var data uint64
+				if fields[0] == wanted.inProc {
+					wanted_field := wanted.field
+					// if not set, assume field[1]. Shouldn't be field[0], as
+					// that's a string
+					if wanted_field == 0 {
+						wanted_field = 1
+					}
+					data, err = strconv.ParseUint((fields[wanted_field]), 10, 64)
+					if err != nil {
+						return err
+					}
+					report_name := wanted.inProc
+					if wanted.reportAs != "" {
+						report_name = wanted.reportAs
+					}
+					acc.Add(report_name, data, tags)
+
+				}
+			}
+		}
+	}
+	return nil
+}
+
+// SampleConfig returns sample configuration message
+func (l *Lustre2) SampleConfig() string {
+	return sampleConfig
+}
+
+// Description returns description of Lustre2 plugin
+func (l *Lustre2) Description() string {
+	return "Read metrics from local Lustre service on OST, MDS"
+}
+
+// Gather reads stats from all lustre targets
+func (l *Lustre2) Gather(acc plugins.Accumulator) error {
+
+	if len(l.Ost_procfiles) == 0 {
+		// read/write bytes are in obdfilter/<ost_name>/stats
+		err := l.GetLustreProcStats("/proc/fs/lustre/obdfilter/*/stats", wanted_ost_fields, acc)
+		if err != nil {
+			return err
+		}
+		// cache counters are in osd-ldiskfs/<ost_name>/stats
+		err = l.GetLustreProcStats("/proc/fs/lustre/osd-ldiskfs/*/stats", wanted_ost_fields, acc)
+		if err != nil {
+			return err
+		}
+	}
+
+	if len(l.Mds_procfiles) == 0 {
+		// Metadata server stats
+		err := l.GetLustreProcStats("/proc/fs/lustre/mdt/*/md_stats", wanted_mds_fields, acc)
+		if err != nil {
+			return err
+		}
+	}
+
+	for _, procfile := range l.Ost_procfiles {
+		err := l.GetLustreProcStats(procfile, wanted_ost_fields, acc)
+		if err != nil {
+			return err
+		}
+	}
+	for _, procfile := range l.Mds_procfiles {
+		err := l.GetLustreProcStats(procfile, wanted_mds_fields, acc)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func init() {
+	plugins.Add("lustre2", func() plugins.Plugin {
+		return &Lustre2{}
+	})
+}