client_golang/prometheus/process_collector.go

148 lines
4.1 KiB
Go

// Copyright 2015 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.
package prometheus
import "github.com/prometheus/procfs"
type processCollector struct {
collectFn func(chan<- Metric)
pidFn func() (int, error)
cpuTotal *Desc
openFDs, maxFDs *Desc
vsize, maxVsize *Desc
rss *Desc
startTime *Desc
}
// NewProcessCollector returns a collector which exports the current state of
// process metrics including CPU, memory and file descriptor usage as well as
// the process start time for the given process ID under the given namespace.
//
// Currently, the collector depends on a Linux-style proc filesystem and
// therefore only exports metrics for Linux.
func NewProcessCollector(pid int, namespace string) Collector {
return NewProcessCollectorPIDFn(
func() (int, error) { return pid, nil },
namespace,
)
}
// NewProcessCollectorPIDFn works like NewProcessCollector but the process ID is
// determined on each collect anew by calling the given pidFn function.
func NewProcessCollectorPIDFn(
pidFn func() (int, error),
namespace string,
) Collector {
ns := ""
if len(namespace) > 0 {
ns = namespace + "_"
}
c := processCollector{
pidFn: pidFn,
collectFn: func(chan<- Metric) {},
cpuTotal: NewDesc(
ns+"process_cpu_seconds_total",
"Total user and system CPU time spent in seconds.",
nil, nil,
),
openFDs: NewDesc(
ns+"process_open_fds",
"Number of open file descriptors.",
nil, nil,
),
maxFDs: NewDesc(
ns+"process_max_fds",
"Maximum number of open file descriptors.",
nil, nil,
),
vsize: NewDesc(
ns+"process_virtual_memory_bytes",
"Virtual memory size in bytes.",
nil, nil,
),
maxVsize: NewDesc(
ns+"process_max_virtual_memory_bytes",
"Maximum amount of virtual memory available in bytes.",
nil, nil,
),
rss: NewDesc(
ns+"process_resident_memory_bytes",
"Resident memory size in bytes.",
nil, nil,
),
startTime: NewDesc(
ns+"process_start_time_seconds",
"Start time of the process since unix epoch in seconds.",
nil, nil,
),
}
// Set up process metric collection if supported by the runtime.
if _, err := procfs.NewStat(); err == nil {
c.collectFn = c.processCollect
}
return &c
}
// Describe returns all descriptions of the collector.
func (c *processCollector) Describe(ch chan<- *Desc) {
ch <- c.cpuTotal
ch <- c.openFDs
ch <- c.maxFDs
ch <- c.vsize
ch <- c.maxVsize
ch <- c.rss
ch <- c.startTime
}
// Collect returns the current state of all metrics of the collector.
func (c *processCollector) Collect(ch chan<- Metric) {
c.collectFn(ch)
}
// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
// client allows users to configure the error behavior.
func (c *processCollector) processCollect(ch chan<- Metric) {
pid, err := c.pidFn()
if err != nil {
return
}
p, err := procfs.NewProc(pid)
if err != nil {
return
}
if stat, err := p.NewStat(); err == nil {
ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
if startTime, err := stat.StartTime(); err == nil {
ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
}
}
if fds, err := p.FileDescriptorsLen(); err == nil {
ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
}
if limits, err := p.NewLimits(); err == nil {
ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
ch <- MustNewConstMetric(c.maxVsize, GaugeValue, float64(limits.AddressSpace))
}
}