ZFS Collector: Add dmu_tx functionality

Signed-Off-By: Joe Handzik <joseph.t.handzik@hpe.com>

collector/fixtures/e2e-output.txt

@@ -2350,6 +2350,39 @@ node_zfsArc_prefetch_metadata_misses 16071
 # HELP node_zfsArc_size kstat.zfs.misc.arcstats.size
 # TYPE node_zfsArc_size untyped
 node_zfsArc_size 1.603939792e+09
+# HELP node_zfsDmuTx_dmu_tx_assigned kstat.zfs.misc.dmu_tx.dmu_tx_assigned
+# TYPE node_zfsDmuTx_dmu_tx_assigned untyped
+node_zfsDmuTx_dmu_tx_assigned 3.532844e+06
+# HELP node_zfsDmuTx_dmu_tx_delay kstat.zfs.misc.dmu_tx.dmu_tx_delay
+# TYPE node_zfsDmuTx_dmu_tx_delay untyped
+node_zfsDmuTx_dmu_tx_delay 0
+# HELP node_zfsDmuTx_dmu_tx_dirty_delay kstat.zfs.misc.dmu_tx.dmu_tx_dirty_delay
+# TYPE node_zfsDmuTx_dmu_tx_dirty_delay untyped
+node_zfsDmuTx_dmu_tx_dirty_delay 0
+# HELP node_zfsDmuTx_dmu_tx_dirty_over_max kstat.zfs.misc.dmu_tx.dmu_tx_dirty_over_max
+# TYPE node_zfsDmuTx_dmu_tx_dirty_over_max untyped
+node_zfsDmuTx_dmu_tx_dirty_over_max 0
+# HELP node_zfsDmuTx_dmu_tx_dirty_throttle kstat.zfs.misc.dmu_tx.dmu_tx_dirty_throttle
+# TYPE node_zfsDmuTx_dmu_tx_dirty_throttle untyped
+node_zfsDmuTx_dmu_tx_dirty_throttle 0
+# HELP node_zfsDmuTx_dmu_tx_error kstat.zfs.misc.dmu_tx.dmu_tx_error
+# TYPE node_zfsDmuTx_dmu_tx_error untyped
+node_zfsDmuTx_dmu_tx_error 0
+# HELP node_zfsDmuTx_dmu_tx_group kstat.zfs.misc.dmu_tx.dmu_tx_group
+# TYPE node_zfsDmuTx_dmu_tx_group untyped
+node_zfsDmuTx_dmu_tx_group 0
+# HELP node_zfsDmuTx_dmu_tx_memory_reclaim kstat.zfs.misc.dmu_tx.dmu_tx_memory_reclaim
+# TYPE node_zfsDmuTx_dmu_tx_memory_reclaim untyped
+node_zfsDmuTx_dmu_tx_memory_reclaim 0
+# HELP node_zfsDmuTx_dmu_tx_memory_reserve kstat.zfs.misc.dmu_tx.dmu_tx_memory_reserve
+# TYPE node_zfsDmuTx_dmu_tx_memory_reserve untyped
+node_zfsDmuTx_dmu_tx_memory_reserve 0
+# HELP node_zfsDmuTx_dmu_tx_quota kstat.zfs.misc.dmu_tx.dmu_tx_quota
+# TYPE node_zfsDmuTx_dmu_tx_quota untyped
+node_zfsDmuTx_dmu_tx_quota 0
+# HELP node_zfsDmuTx_dmu_tx_suspended kstat.zfs.misc.dmu_tx.dmu_tx_suspended
+# TYPE node_zfsDmuTx_dmu_tx_suspended untyped
+node_zfsDmuTx_dmu_tx_suspended 0
 # HELP node_zfsFetch_bogus_streams kstat.zfs.misc.zfetchstats.bogus_streams
 # TYPE node_zfsFetch_bogus_streams untyped
 node_zfsFetch_bogus_streams 0

collector/fixtures/proc/spl/kstat/zfs/dmu_tx

@@ -0,0 +1,13 @@
+5 1 0x01 11 528 8010436841 354962070418194
+name                            type data
+dmu_tx_assigned                 4    3532844
+dmu_tx_delay                    4    0
+dmu_tx_error                    4    0
+dmu_tx_suspended                4    0
+dmu_tx_group                    4    0
+dmu_tx_memory_reserve           4    0
+dmu_tx_memory_reclaim           4    0
+dmu_tx_dirty_throttle           4    0
+dmu_tx_dirty_delay              4    0
+dmu_tx_dirty_over_max           4    0
+dmu_tx_quota                    4    0

collector/zfs.go

@@ -35,6 +35,7 @@ type zfsSubsystemName string
 
 const (
 	arc            = zfsSubsystemName("zfsArc")
+	dmuTx          = zfsSubsystemName("zfsDmuTx")
 	fm             = zfsSubsystemName("zfsFm")
 	vdevCache      = zfsSubsystemName("zfsVdevCache")
 	xuio           = zfsSubsystemName("zfsXuio")
@@ -78,23 +79,39 @@ func (c *zfsCollector) Update(ch chan<- prometheus.Metric) (err error) {
 
 	// Zfetchstats
 	err = c.updateZfetchstats(ch)
-	if err != nil { return err }
+	if err != nil {
+		return err
+	}
 
 	// Zil
 	err = c.updateZil(ch)
-	if err != nil { return err }
+	if err != nil {
+		return err
+	}
 
 	// VdevCacheStats
 	err = c.updateVdevCacheStats(ch)
-	if err != nil { return err }
+	if err != nil {
+		return err
+	}
 
 	// XuioStats
 	err = c.updateXuioStats(ch)
-	if err != nil { return err }
+	if err != nil {
+		return err
+	}
 
 	// Fm
 	err = c.updateFm(ch)
-	if err != nil { return err }
+	if err != nil {
+		return err
+	}
+
+	// DmuTx
+	err = c.updateDmuTx(ch)
+	if err != nil {
+		return err
+	}
 
 	// Pool stats
 	return c.updatePoolStats(ch)

collector/zfs_linux.go

@@ -29,6 +29,7 @@ import (
 const (
 	zfsProcpathBase      = "spl/kstat/zfs/"
 	zfsArcstatsExt       = "arcstats"
+	zfsDmuTxExt          = "dmu_tx"
 	zfsFmExt             = "fm"
 	zfsFetchstatsExt     = "zfetchstats"
 	zfsVdevCacheStatsExt = "vdev_cache_stats"
@@ -117,7 +118,19 @@ func (c *zfsCollector) updateFm(ch chan<- prometheus.Metric) (err error) {
 	})
 }
 
-func (c *zfsCollector) parseProcfsFile(reader io.Reader, fmt_ext string, handler func(zfsSysctl, zfsMetricValue)) (err error) {
+func (c *zfsCollector) updateDmuTx(ch chan<- prometheus.Metric) (err error) {
+	file, err := c.openProcFile(filepath.Join(zfsProcpathBase, zfsDmuTxExt))
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	return c.parseProcfsFile(file, zfsDmuTxExt, func(s zfsSysctl, v zfsMetricValue) {
+		ch <- c.constSysctlMetric(dmuTx, s, v)
+	})
+}
+
+func (c *zfsCollector) parseProcfsFile(reader io.Reader, fmtExt string, handler func(zfsSysctl, zfsMetricValue)) (err error) {
 	scanner := bufio.NewScanner(reader)
 
 	parseLine := false
@@ -135,7 +148,7 @@ func (c *zfsCollector) parseProcfsFile(reader io.Reader, fmt_ext string, handler
 			continue
 		}
 
-		key := fmt.Sprintf("kstat.zfs.misc.%s.%s", fmt_ext, parts[0])
+		key := fmt.Sprintf("kstat.zfs.misc.%s.%s", fmtExt, parts[0])
 
 		value, err := strconv.Atoi(parts[2])
 		if err != nil {
@@ -145,7 +158,7 @@ func (c *zfsCollector) parseProcfsFile(reader io.Reader, fmt_ext string, handler
 
 	}
 	if !parseLine {
-		return fmt.Errorf("did not parse a single %q metric", fmt_ext)
+		return fmt.Errorf("did not parse a single %q metric", fmtExt)
 	}
 
 	return scanner.Err()

collector/zfs_linux_test.go

@@ -233,3 +233,39 @@ func TestFmParsing(t *testing.T) {
 		t.Fatal("Fm parsing handler was not called for some expected sysctls")
 	}
 }
+
+func TestDmuTxParsing(t *testing.T) {
+	dmuTxFile, err := os.Open("fixtures/proc/spl/kstat/zfs/dmu_tx")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer dmuTxFile.Close()
+
+	c := zfsCollector{}
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	handlerCalled := false
+	err = c.parseProcfsFile(dmuTxFile, "dmu_tx", func(s zfsSysctl, v zfsMetricValue) {
+
+		if s != zfsSysctl("kstat.zfs.misc.dmu_tx.dmu_tx_assigned") {
+			return
+		}
+
+		handlerCalled = true
+
+		if v != zfsMetricValue(3532844) {
+			t.Fatalf("Incorrect value parsed from procfs data")
+		}
+
+	})
+
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !handlerCalled {
+		t.Fatal("DmuTx parsing handler was not called for some expected sysctls")
+	}
+}