Issue influxdata#2616: ZFS Zpool properties on Linux

plugins/inputs/zfs/README.md

@@ -1,7 +1,7 @@
 # ZFS plugin
 
 This ZFS plugin provides metrics from your ZFS filesystems. It supports ZFS on
-Linux and FreeBSD. It gets ZFS stat from `/proc/spl/kstat/zfs` on Linux and
+Linux and FreeBSD. It gets ZFS stat from `/proc/spl/kstat/zfs` and zpool on Linux and
 from `sysctl` and `zpool` on FreeBSD.
 
 ### Configuration:
@@ -180,7 +180,7 @@ each pool.
 
 #### Pool Metrics (optional)
 
-On Linux (reference: kstat accumulated time and queue length statistics):
+On Linux (reference: kstat accumulated time and queue length statistics) and zpool statistics:
 
 - zfs_pool
     - nread (integer, bytes)
@@ -195,6 +195,12 @@ On Linux (reference: kstat accumulated time and queue length statistics):
     - rupdate (integer, timestamp)
     - wcnt (integer, count)
     - rcnt (integer, count)
+    - allocated (integer, bytes)
+    - capacity (integer, bytes)
+    - dedupratio (float, ratio)
+    - free (integer, bytes)
+    - size (integer, bytes)
+    - fragmentation (integer, percent)
 
 On FreeBSD:
 

plugins/inputs/zfs/zfs.go

@@ -1,5 +1,13 @@
 package zfs
 
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
 type Sysctl func(metric string) ([]string, error)
 type Zpool func() ([]string, error)
 
@@ -30,6 +38,97 @@ func (z *Zfs) SampleConfig() string {
 	return sampleConfig
 }
 
+func (z *Zfs) getZpoolStats() (map[string]map[string]interface{}, error) {
+
+	poolFields := map[string]map[string]interface{}{}
+
+	lines, err := z.zpool()
+	if err != nil {
+		return poolFields, err
+	}
+
+	for _, line := range lines {
+		col := strings.Split(line, "\t")
+		if len(col) != 8 {
+			continue
+		}
+
+		health := col[1]
+		name := col[0]
+
+		fields := map[string]interface{}{
+			"name":   name,
+			"health": health,
+		}
+
+		if health == "UNAVAIL" {
+
+			fields["size"] = int64(0)
+
+		} else {
+
+			size, err := strconv.ParseInt(col[2], 10, 64)
+			if err != nil {
+				return poolFields, fmt.Errorf("Error parsing size: %s", err)
+			}
+			fields["size"] = size
+
+			alloc, err := strconv.ParseInt(col[3], 10, 64)
+			if err != nil {
+				return poolFields, fmt.Errorf("Error parsing allocation: %s", err)
+			}
+			fields["allocated"] = alloc
+
+			free, err := strconv.ParseInt(col[4], 10, 64)
+			if err != nil {
+				return poolFields, fmt.Errorf("Error parsing free: %s", err)
+			}
+			fields["free"] = free
+
+			frag, err := strconv.ParseInt(strings.TrimSuffix(col[5], "%"), 10, 0)
+			if err != nil { // This might be - for RO devs
+				frag = 0
+			}
+			fields["fragmentation"] = frag
+
+			capval, err := strconv.ParseInt(col[6], 10, 0)
+			if err != nil {
+				return poolFields, fmt.Errorf("Error parsing capacity: %s", err)
+			}
+			fields["capacity"] = capval
+
+			dedup, err := strconv.ParseFloat(strings.TrimSuffix(col[7], "x"), 32)
+			if err != nil {
+				return poolFields, fmt.Errorf("Error parsing dedupratio: %s", err)
+			}
+			fields["dedupratio"] = dedup
+		}
+		poolFields[name] = fields
+	}
+
+	return poolFields, nil
+}
+
 func (z *Zfs) Description() string {
 	return "Read metrics of ZFS from arcstats, zfetchstats, vdev_cache_stats, and pools"
 }
+
+func run(command string, args ...string) ([]string, error) {
+	cmd := exec.Command(command, args...)
+	var outbuf, errbuf bytes.Buffer
+	cmd.Stdout = &outbuf
+	cmd.Stderr = &errbuf
+	err := cmd.Run()
+
+	stdout := strings.TrimSpace(outbuf.String())
+	stderr := strings.TrimSpace(errbuf.String())
+
+	if _, ok := err.(*exec.ExitError); ok {
+		return nil, fmt.Errorf("%s error: %s", command, stderr)
+	}
+	return strings.Split(stdout, "\n"), nil
+}
+
+func zpool() ([]string, error) {
+	return run("zpool", []string{"list", "-Hp", "-o", "name,health,size,alloc,free,fragmentation,capacity,dedupratio"}...)
+}

plugins/inputs/zfs/zfs_freebsd.go

@@ -3,9 +3,7 @@
 package zfs
 
 import (
-	"bytes"
 	"fmt"
-	"os/exec"
 	"strconv"
 	"strings"
 
@@ -14,71 +12,25 @@ import (
 )
 
 func (z *Zfs) gatherPoolStats(acc telegraf.Accumulator) (string, error) {
-
-	lines, err := z.zpool()
+	poolFields, err := z.getZpoolStats()
 	if err != nil {
 		return "", err
 	}
 
 	pools := []string{}
-	for _, line := range lines {
-		col := strings.Split(line, "\t")
-
-		pools = append(pools, col[0])
+	for name, _ := range poolFields {
+		pools = append(pools, name)
 	}
 
 	if z.PoolMetrics {
-		for _, line := range lines {
-			col := strings.Split(line, "\t")
-			if len(col) != 8 {
-				continue
+		for name, fields := range poolFields {
+			tags := map[string]string{
+				"pool":   name,
+				"health": fields["health"].(string),
 			}
 
-			tags := map[string]string{"pool": col[0], "health": col[1]}
-			fields := map[string]interface{}{}
-
-			if tags["health"] == "UNAVAIL" {
-
-				fields["size"] = int64(0)
-
-			} else {
-
-				size, err := strconv.ParseInt(col[2], 10, 64)
-				if err != nil {
-					return "", fmt.Errorf("Error parsing size: %s", err)
-				}
-				fields["size"] = size
-
-				alloc, err := strconv.ParseInt(col[3], 10, 64)
-				if err != nil {
-					return "", fmt.Errorf("Error parsing allocation: %s", err)
-				}
-				fields["allocated"] = alloc
-
-				free, err := strconv.ParseInt(col[4], 10, 64)
-				if err != nil {
-					return "", fmt.Errorf("Error parsing free: %s", err)
-				}
-				fields["free"] = free
-
-				frag, err := strconv.ParseInt(strings.TrimSuffix(col[5], "%"), 10, 0)
-				if err != nil { // This might be - for RO devs
-					frag = 0
-				}
-				fields["fragmentation"] = frag
-
-				capval, err := strconv.ParseInt(col[6], 10, 0)
-				if err != nil {
-					return "", fmt.Errorf("Error parsing capacity: %s", err)
-				}
-				fields["capacity"] = capval
-
-				dedup, err := strconv.ParseFloat(strings.TrimSuffix(col[7], "x"), 32)
-				if err != nil {
-					return "", fmt.Errorf("Error parsing dedupratio: %s", err)
-				}
-				fields["dedupratio"] = dedup
-			}
+			delete(fields, "name")
+			delete(fields, "health")
 
 			acc.AddFields("zfs_pool", fields, tags)
 		}
@@ -93,11 +45,11 @@ func (z *Zfs) Gather(acc telegraf.Accumulator) error {
 		kstatMetrics = []string{"arcstats", "zfetchstats", "vdev_cache_stats"}
 	}
 
-	tags := map[string]string{}
 	poolNames, err := z.gatherPoolStats(acc)
 	if err != nil {
 		return err
 	}
+	tags := map[string]string{"pools": poolNames}
 	tags["pools"] = poolNames
 
 	fields := make(map[string]interface{})
@@ -117,26 +69,6 @@ func (z *Zfs) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func run(command string, args ...string) ([]string, error) {
-	cmd := exec.Command(command, args...)
-	var outbuf, errbuf bytes.Buffer
-	cmd.Stdout = &outbuf
-	cmd.Stderr = &errbuf
-	err := cmd.Run()
-
-	stdout := strings.TrimSpace(outbuf.String())
-	stderr := strings.TrimSpace(errbuf.String())
-
-	if _, ok := err.(*exec.ExitError); ok {
-		return nil, fmt.Errorf("%s error: %s", command, stderr)
-	}
-	return strings.Split(stdout, "\n"), nil
-}
-
-func zpool() ([]string, error) {
-	return run("zpool", []string{"list", "-Hp", "-o", "name,health,size,alloc,free,fragmentation,capacity,dedupratio"}...)
-}
-
 func sysctl(metric string) ([]string, error) {
 	return run("sysctl", []string{"-q", fmt.Sprintf("kstat.zfs.misc.%s", metric)}...)
 }