Add softnet collector (#1576)

Signed-off-by: Peter Nicholson <petergoods@hotmail.com>

CHANGELOG.md

@@ -21,6 +21,7 @@
 * [FEATURE] Add new metric node_cpu_info #1489
 * [FEATURE] Add new thermal_zone collector #1425
 * [FEATURE] Add new cooling_device metrics to thermal zone collector #1445
+* [FEATURE] Add new softnet collector #1576
 * [ENHANCEMENT] Collect InfiniBand port state and physical state #1357
 * [ENHANCEMENT] Include additional XFS runtime statistics. #1423
 * [ENHANCEMENT] Report non-fatal collection errors in the exporter metric. #1439

README.md

@@ -53,6 +53,7 @@ nfsd | Exposes NFS kernel server statistics from `/proc/net/rpc/nfsd`. This is t
 pressure | Exposes pressure stall statistics from `/proc/pressure/`. | Linux (kernel 4.20+ and/or [CONFIG\_PSI](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/accounting/psi.txt))
 schedstat | Exposes task scheduler statistics from `/proc/schedstat`. | Linux
 sockstat | Exposes various statistics from `/proc/net/sockstat`. | Linux
+softnet | Exposes statistics from `/proc/net/softnet_stat`. | Linux
 stat | Exposes various statistics from `/proc/stat`. This includes boot time, forks and interrupts. | Linux
 textfile | Exposes statistics read from local disk. The `--collector.textfile.directory` flag must be set. | _any_
 thermal\_zone | Exposes thermal zone & cooling device statistics from `/sys/class/thermal`. | Linux

collector/fixtures/e2e-64k-page-output.txt

@@ -2547,6 +2547,7 @@ node_scrape_collector_success{collector="processes"} 1
 node_scrape_collector_success{collector="qdisc"} 1
 node_scrape_collector_success{collector="schedstat"} 1
 node_scrape_collector_success{collector="sockstat"} 1
+node_scrape_collector_success{collector="softnet"} 1
 node_scrape_collector_success{collector="stat"} 1
 node_scrape_collector_success{collector="textfile"} 1
 node_scrape_collector_success{collector="thermal_zone"} 1
@@ -2596,6 +2597,24 @@ node_sockstat_UDP_mem_bytes 0
 # HELP node_sockstat_sockets_used Number of sockets sockets in state used.
 # TYPE node_sockstat_sockets_used gauge
 node_sockstat_sockets_used 229
+# HELP node_softnet_dropped_total Number of dropped packets
+# TYPE node_softnet_dropped_total counter
+node_softnet_dropped_total{cpu="0"} 0
+node_softnet_dropped_total{cpu="1"} 41
+node_softnet_dropped_total{cpu="2"} 0
+node_softnet_dropped_total{cpu="3"} 0
+# HELP node_softnet_processed_total Number of processed packets
+# TYPE node_softnet_processed_total counter
+node_softnet_processed_total{cpu="0"} 299641
+node_softnet_processed_total{cpu="1"} 916354
+node_softnet_processed_total{cpu="2"} 5.577791e+06
+node_softnet_processed_total{cpu="3"} 3.113785e+06
+# HELP node_softnet_times_squeezed_total Number of times processing packets ran out of quota
+# TYPE node_softnet_times_squeezed_total counter
+node_softnet_times_squeezed_total{cpu="0"} 1
+node_softnet_times_squeezed_total{cpu="1"} 10
+node_softnet_times_squeezed_total{cpu="2"} 85
+node_softnet_times_squeezed_total{cpu="3"} 50
 # HELP node_textfile_mtime_seconds Unixtime mtime of textfiles successfully read.
 # TYPE node_textfile_mtime_seconds gauge
 # HELP node_textfile_scrape_error 1 if there was an error opening or reading a file, 0 otherwise

collector/fixtures/e2e-output.txt

@@ -2568,6 +2568,7 @@ node_scrape_collector_success{collector="processes"} 1
 node_scrape_collector_success{collector="qdisc"} 1
 node_scrape_collector_success{collector="schedstat"} 1
 node_scrape_collector_success{collector="sockstat"} 1
+node_scrape_collector_success{collector="softnet"} 1
 node_scrape_collector_success{collector="stat"} 1
 node_scrape_collector_success{collector="textfile"} 1
 node_scrape_collector_success{collector="thermal_zone"} 1
@@ -2635,6 +2636,24 @@ node_sockstat_UDP_mem_bytes 0
 # HELP node_sockstat_sockets_used Number of IPv4 sockets in use.
 # TYPE node_sockstat_sockets_used gauge
 node_sockstat_sockets_used 229
+# HELP node_softnet_dropped_total Number of dropped packets
+# TYPE node_softnet_dropped_total counter
+node_softnet_dropped_total{cpu="0"} 0
+node_softnet_dropped_total{cpu="1"} 41
+node_softnet_dropped_total{cpu="2"} 0
+node_softnet_dropped_total{cpu="3"} 0
+# HELP node_softnet_processed_total Number of processed packets
+# TYPE node_softnet_processed_total counter
+node_softnet_processed_total{cpu="0"} 299641
+node_softnet_processed_total{cpu="1"} 916354
+node_softnet_processed_total{cpu="2"} 5.577791e+06
+node_softnet_processed_total{cpu="3"} 3.113785e+06
+# HELP node_softnet_times_squeezed_total Number of times processing packets ran out of quota
+# TYPE node_softnet_times_squeezed_total counter
+node_softnet_times_squeezed_total{cpu="0"} 1
+node_softnet_times_squeezed_total{cpu="1"} 10
+node_softnet_times_squeezed_total{cpu="2"} 85
+node_softnet_times_squeezed_total{cpu="3"} 50
 # HELP node_textfile_mtime_seconds Unixtime mtime of textfiles successfully read.
 # TYPE node_textfile_mtime_seconds gauge
 # HELP node_textfile_scrape_error 1 if there was an error opening or reading a file, 0 otherwise

collector/fixtures/proc/net/softnet_stat

@@ -0,0 +1,4 @@
+00049279 00000000 00000001 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+000dfb82 00000029 0000000a 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+00551c3f 00000000 00000055 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
+002f8339 00000000 00000032 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000

collector/softnet_linux.go

@@ -0,0 +1,99 @@
+// Copyright 2019 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build !nosoftnet
+
+package collector
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/procfs"
+)
+
+type softnetCollector struct {
+	fs           procfs.FS
+	processed    *prometheus.Desc
+	dropped      *prometheus.Desc
+	timeSqueezed *prometheus.Desc
+}
+
+const (
+	softnetSubsystem = "softnet"
+)
+
+func init() {
+	registerCollector("softnet", defaultEnabled, NewSoftnetCollector)
+}
+
+// NewSoftnetCollector returns a new Collector exposing softnet metrics.
+func NewSoftnetCollector() (Collector, error) {
+	fs, err := procfs.NewFS(*procPath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open procfs: %w", err)
+	}
+
+	return &softnetCollector{
+		fs: fs,
+		processed: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, softnetSubsystem, "processed_total"),
+			"Number of processed packets",
+			[]string{"cpu"}, nil,
+		),
+		dropped: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, softnetSubsystem, "dropped_total"),
+			"Number of dropped packets",
+			[]string{"cpu"}, nil,
+		),
+		timeSqueezed: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, softnetSubsystem, "times_squeezed_total"),
+			"Number of times processing packets ran out of quota",
+			[]string{"cpu"}, nil,
+		),
+	}, nil
+}
+
+// Update gets parsed softnet statistics using procfs.
+func (c *softnetCollector) Update(ch chan<- prometheus.Metric) error {
+	stats, err := c.fs.GatherSoftnetStats()
+	if err != nil {
+		return fmt.Errorf("could not get softnet statistics: %s", err)
+	}
+
+	for cpuNumber, cpuStats := range stats {
+		cpu := strconv.Itoa(cpuNumber)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.processed,
+			prometheus.CounterValue,
+			float64(cpuStats.Processed),
+			cpu,
+		)
+		ch <- prometheus.MustNewConstMetric(
+			c.dropped,
+			prometheus.CounterValue,
+			float64(cpuStats.Dropped),
+			cpu,
+		)
+		ch <- prometheus.MustNewConstMetric(
+			c.timeSqueezed,
+			prometheus.CounterValue,
+			float64(cpuStats.TimeSqueezed),
+			cpu,
+		)
+	}
+
+	return nil
+}