| // Copyright 2018 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 ( |
| "fmt" |
| "runtime" |
| "runtime/debug" |
| "time" |
| ) |
| |
| type goCollector struct { |
| goroutinesDesc *Desc |
| threadsDesc *Desc |
| gcDesc *Desc |
| goInfoDesc *Desc |
| |
| // metrics to describe and collect |
| metrics memStatsMetrics |
| } |
| |
| // NewGoCollector returns a collector which exports metrics about the current Go |
| // process. This includes memory stats. To collect those, runtime.ReadMemStats |
| // is called. This causes a stop-the-world, which is very short with Go1.9+ |
| // (~25µs). However, with older Go versions, the stop-the-world duration depends |
| // on the heap size and can be quite significant (~1.7 ms/GiB as per |
| // https://go-review.googlesource.com/c/go/+/34937). |
| func NewGoCollector() Collector { |
| return &goCollector{ |
| goroutinesDesc: NewDesc( |
| "go_goroutines", |
| "Number of goroutines that currently exist.", |
| nil, nil), |
| threadsDesc: NewDesc( |
| "go_threads", |
| "Number of OS threads created.", |
| nil, nil), |
| gcDesc: NewDesc( |
| "go_gc_duration_seconds", |
| "A summary of the GC invocation durations.", |
| nil, nil), |
| goInfoDesc: NewDesc( |
| "go_info", |
| "Information about the Go environment.", |
| nil, Labels{"version": runtime.Version()}), |
| metrics: memStatsMetrics{ |
| { |
| desc: NewDesc( |
| memstatNamespace("alloc_bytes"), |
| "Number of bytes allocated and still in use.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("alloc_bytes_total"), |
| "Total number of bytes allocated, even if freed.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) }, |
| valType: CounterValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("sys_bytes"), |
| "Number of bytes obtained from system.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.Sys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("lookups_total"), |
| "Total number of pointer lookups.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) }, |
| valType: CounterValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("mallocs_total"), |
| "Total number of mallocs.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) }, |
| valType: CounterValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("frees_total"), |
| "Total number of frees.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.Frees) }, |
| valType: CounterValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_alloc_bytes"), |
| "Number of heap bytes allocated and still in use.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_sys_bytes"), |
| "Number of heap bytes obtained from system.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_idle_bytes"), |
| "Number of heap bytes waiting to be used.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_inuse_bytes"), |
| "Number of heap bytes that are in use.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_released_bytes"), |
| "Number of heap bytes released to OS.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("heap_objects"), |
| "Number of allocated objects.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("stack_inuse_bytes"), |
| "Number of bytes in use by the stack allocator.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("stack_sys_bytes"), |
| "Number of bytes obtained from system for stack allocator.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("mspan_inuse_bytes"), |
| "Number of bytes in use by mspan structures.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("mspan_sys_bytes"), |
| "Number of bytes used for mspan structures obtained from system.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("mcache_inuse_bytes"), |
| "Number of bytes in use by mcache structures.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("mcache_sys_bytes"), |
| "Number of bytes used for mcache structures obtained from system.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("buck_hash_sys_bytes"), |
| "Number of bytes used by the profiling bucket hash table.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("gc_sys_bytes"), |
| "Number of bytes used for garbage collection system metadata.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("other_sys_bytes"), |
| "Number of bytes used for other system allocations.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("next_gc_bytes"), |
| "Number of heap bytes when next garbage collection will take place.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("last_gc_time_seconds"), |
| "Number of seconds since 1970 of last garbage collection.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 }, |
| valType: GaugeValue, |
| }, { |
| desc: NewDesc( |
| memstatNamespace("gc_cpu_fraction"), |
| "The fraction of this program's available CPU time used by the GC since the program started.", |
| nil, nil, |
| ), |
| eval: func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction }, |
| valType: GaugeValue, |
| }, |
| }, |
| } |
| } |
| |
| func memstatNamespace(s string) string { |
| return fmt.Sprintf("go_memstats_%s", s) |
| } |
| |
| // Describe returns all descriptions of the collector. |
| func (c *goCollector) Describe(ch chan<- *Desc) { |
| ch <- c.goroutinesDesc |
| ch <- c.threadsDesc |
| ch <- c.gcDesc |
| ch <- c.goInfoDesc |
| for _, i := range c.metrics { |
| ch <- i.desc |
| } |
| } |
| |
| // Collect returns the current state of all metrics of the collector. |
| func (c *goCollector) Collect(ch chan<- Metric) { |
| ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine())) |
| n, _ := runtime.ThreadCreateProfile(nil) |
| ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n)) |
| |
| var stats debug.GCStats |
| stats.PauseQuantiles = make([]time.Duration, 5) |
| debug.ReadGCStats(&stats) |
| |
| quantiles := make(map[float64]float64) |
| for idx, pq := range stats.PauseQuantiles[1:] { |
| quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds() |
| } |
| quantiles[0.0] = stats.PauseQuantiles[0].Seconds() |
| ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles) |
| |
| ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1) |
| |
| ms := &runtime.MemStats{} |
| runtime.ReadMemStats(ms) |
| for _, i := range c.metrics { |
| ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms)) |
| } |
| } |
| |
| // memStatsMetrics provide description, value, and value type for memstat metrics. |
| type memStatsMetrics []struct { |
| desc *Desc |
| eval func(*runtime.MemStats) float64 |
| valType ValueType |
| } |