khenaidoo | ffe076b | 2019-01-15 16:08:08 -0500 | [diff] [blame^] | 1 | // Copyright 2018 The Prometheus Authors |
| 2 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 3 | // you may not use this file except in compliance with the License. |
| 4 | // You may obtain a copy of the License at |
| 5 | // |
| 6 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 7 | // |
| 8 | // Unless required by applicable law or agreed to in writing, software |
| 9 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 10 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 11 | // See the License for the specific language governing permissions and |
| 12 | // limitations under the License. |
| 13 | |
| 14 | package prometheus |
| 15 | |
| 16 | import ( |
| 17 | "fmt" |
| 18 | "runtime" |
| 19 | "runtime/debug" |
| 20 | "time" |
| 21 | ) |
| 22 | |
| 23 | type goCollector struct { |
| 24 | goroutinesDesc *Desc |
| 25 | threadsDesc *Desc |
| 26 | gcDesc *Desc |
| 27 | goInfoDesc *Desc |
| 28 | |
| 29 | // metrics to describe and collect |
| 30 | metrics memStatsMetrics |
| 31 | } |
| 32 | |
| 33 | // NewGoCollector returns a collector which exports metrics about the current Go |
| 34 | // process. This includes memory stats. To collect those, runtime.ReadMemStats |
| 35 | // is called. This causes a stop-the-world, which is very short with Go1.9+ |
| 36 | // (~25µs). However, with older Go versions, the stop-the-world duration depends |
| 37 | // on the heap size and can be quite significant (~1.7 ms/GiB as per |
| 38 | // https://go-review.googlesource.com/c/go/+/34937). |
| 39 | func NewGoCollector() Collector { |
| 40 | return &goCollector{ |
| 41 | goroutinesDesc: NewDesc( |
| 42 | "go_goroutines", |
| 43 | "Number of goroutines that currently exist.", |
| 44 | nil, nil), |
| 45 | threadsDesc: NewDesc( |
| 46 | "go_threads", |
| 47 | "Number of OS threads created.", |
| 48 | nil, nil), |
| 49 | gcDesc: NewDesc( |
| 50 | "go_gc_duration_seconds", |
| 51 | "A summary of the GC invocation durations.", |
| 52 | nil, nil), |
| 53 | goInfoDesc: NewDesc( |
| 54 | "go_info", |
| 55 | "Information about the Go environment.", |
| 56 | nil, Labels{"version": runtime.Version()}), |
| 57 | metrics: memStatsMetrics{ |
| 58 | { |
| 59 | desc: NewDesc( |
| 60 | memstatNamespace("alloc_bytes"), |
| 61 | "Number of bytes allocated and still in use.", |
| 62 | nil, nil, |
| 63 | ), |
| 64 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) }, |
| 65 | valType: GaugeValue, |
| 66 | }, { |
| 67 | desc: NewDesc( |
| 68 | memstatNamespace("alloc_bytes_total"), |
| 69 | "Total number of bytes allocated, even if freed.", |
| 70 | nil, nil, |
| 71 | ), |
| 72 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) }, |
| 73 | valType: CounterValue, |
| 74 | }, { |
| 75 | desc: NewDesc( |
| 76 | memstatNamespace("sys_bytes"), |
| 77 | "Number of bytes obtained from system.", |
| 78 | nil, nil, |
| 79 | ), |
| 80 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.Sys) }, |
| 81 | valType: GaugeValue, |
| 82 | }, { |
| 83 | desc: NewDesc( |
| 84 | memstatNamespace("lookups_total"), |
| 85 | "Total number of pointer lookups.", |
| 86 | nil, nil, |
| 87 | ), |
| 88 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) }, |
| 89 | valType: CounterValue, |
| 90 | }, { |
| 91 | desc: NewDesc( |
| 92 | memstatNamespace("mallocs_total"), |
| 93 | "Total number of mallocs.", |
| 94 | nil, nil, |
| 95 | ), |
| 96 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) }, |
| 97 | valType: CounterValue, |
| 98 | }, { |
| 99 | desc: NewDesc( |
| 100 | memstatNamespace("frees_total"), |
| 101 | "Total number of frees.", |
| 102 | nil, nil, |
| 103 | ), |
| 104 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.Frees) }, |
| 105 | valType: CounterValue, |
| 106 | }, { |
| 107 | desc: NewDesc( |
| 108 | memstatNamespace("heap_alloc_bytes"), |
| 109 | "Number of heap bytes allocated and still in use.", |
| 110 | nil, nil, |
| 111 | ), |
| 112 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) }, |
| 113 | valType: GaugeValue, |
| 114 | }, { |
| 115 | desc: NewDesc( |
| 116 | memstatNamespace("heap_sys_bytes"), |
| 117 | "Number of heap bytes obtained from system.", |
| 118 | nil, nil, |
| 119 | ), |
| 120 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) }, |
| 121 | valType: GaugeValue, |
| 122 | }, { |
| 123 | desc: NewDesc( |
| 124 | memstatNamespace("heap_idle_bytes"), |
| 125 | "Number of heap bytes waiting to be used.", |
| 126 | nil, nil, |
| 127 | ), |
| 128 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) }, |
| 129 | valType: GaugeValue, |
| 130 | }, { |
| 131 | desc: NewDesc( |
| 132 | memstatNamespace("heap_inuse_bytes"), |
| 133 | "Number of heap bytes that are in use.", |
| 134 | nil, nil, |
| 135 | ), |
| 136 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) }, |
| 137 | valType: GaugeValue, |
| 138 | }, { |
| 139 | desc: NewDesc( |
| 140 | memstatNamespace("heap_released_bytes"), |
| 141 | "Number of heap bytes released to OS.", |
| 142 | nil, nil, |
| 143 | ), |
| 144 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) }, |
| 145 | valType: GaugeValue, |
| 146 | }, { |
| 147 | desc: NewDesc( |
| 148 | memstatNamespace("heap_objects"), |
| 149 | "Number of allocated objects.", |
| 150 | nil, nil, |
| 151 | ), |
| 152 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) }, |
| 153 | valType: GaugeValue, |
| 154 | }, { |
| 155 | desc: NewDesc( |
| 156 | memstatNamespace("stack_inuse_bytes"), |
| 157 | "Number of bytes in use by the stack allocator.", |
| 158 | nil, nil, |
| 159 | ), |
| 160 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) }, |
| 161 | valType: GaugeValue, |
| 162 | }, { |
| 163 | desc: NewDesc( |
| 164 | memstatNamespace("stack_sys_bytes"), |
| 165 | "Number of bytes obtained from system for stack allocator.", |
| 166 | nil, nil, |
| 167 | ), |
| 168 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) }, |
| 169 | valType: GaugeValue, |
| 170 | }, { |
| 171 | desc: NewDesc( |
| 172 | memstatNamespace("mspan_inuse_bytes"), |
| 173 | "Number of bytes in use by mspan structures.", |
| 174 | nil, nil, |
| 175 | ), |
| 176 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) }, |
| 177 | valType: GaugeValue, |
| 178 | }, { |
| 179 | desc: NewDesc( |
| 180 | memstatNamespace("mspan_sys_bytes"), |
| 181 | "Number of bytes used for mspan structures obtained from system.", |
| 182 | nil, nil, |
| 183 | ), |
| 184 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) }, |
| 185 | valType: GaugeValue, |
| 186 | }, { |
| 187 | desc: NewDesc( |
| 188 | memstatNamespace("mcache_inuse_bytes"), |
| 189 | "Number of bytes in use by mcache structures.", |
| 190 | nil, nil, |
| 191 | ), |
| 192 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) }, |
| 193 | valType: GaugeValue, |
| 194 | }, { |
| 195 | desc: NewDesc( |
| 196 | memstatNamespace("mcache_sys_bytes"), |
| 197 | "Number of bytes used for mcache structures obtained from system.", |
| 198 | nil, nil, |
| 199 | ), |
| 200 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) }, |
| 201 | valType: GaugeValue, |
| 202 | }, { |
| 203 | desc: NewDesc( |
| 204 | memstatNamespace("buck_hash_sys_bytes"), |
| 205 | "Number of bytes used by the profiling bucket hash table.", |
| 206 | nil, nil, |
| 207 | ), |
| 208 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) }, |
| 209 | valType: GaugeValue, |
| 210 | }, { |
| 211 | desc: NewDesc( |
| 212 | memstatNamespace("gc_sys_bytes"), |
| 213 | "Number of bytes used for garbage collection system metadata.", |
| 214 | nil, nil, |
| 215 | ), |
| 216 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) }, |
| 217 | valType: GaugeValue, |
| 218 | }, { |
| 219 | desc: NewDesc( |
| 220 | memstatNamespace("other_sys_bytes"), |
| 221 | "Number of bytes used for other system allocations.", |
| 222 | nil, nil, |
| 223 | ), |
| 224 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) }, |
| 225 | valType: GaugeValue, |
| 226 | }, { |
| 227 | desc: NewDesc( |
| 228 | memstatNamespace("next_gc_bytes"), |
| 229 | "Number of heap bytes when next garbage collection will take place.", |
| 230 | nil, nil, |
| 231 | ), |
| 232 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) }, |
| 233 | valType: GaugeValue, |
| 234 | }, { |
| 235 | desc: NewDesc( |
| 236 | memstatNamespace("last_gc_time_seconds"), |
| 237 | "Number of seconds since 1970 of last garbage collection.", |
| 238 | nil, nil, |
| 239 | ), |
| 240 | eval: func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 }, |
| 241 | valType: GaugeValue, |
| 242 | }, { |
| 243 | desc: NewDesc( |
| 244 | memstatNamespace("gc_cpu_fraction"), |
| 245 | "The fraction of this program's available CPU time used by the GC since the program started.", |
| 246 | nil, nil, |
| 247 | ), |
| 248 | eval: func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction }, |
| 249 | valType: GaugeValue, |
| 250 | }, |
| 251 | }, |
| 252 | } |
| 253 | } |
| 254 | |
| 255 | func memstatNamespace(s string) string { |
| 256 | return fmt.Sprintf("go_memstats_%s", s) |
| 257 | } |
| 258 | |
| 259 | // Describe returns all descriptions of the collector. |
| 260 | func (c *goCollector) Describe(ch chan<- *Desc) { |
| 261 | ch <- c.goroutinesDesc |
| 262 | ch <- c.threadsDesc |
| 263 | ch <- c.gcDesc |
| 264 | ch <- c.goInfoDesc |
| 265 | for _, i := range c.metrics { |
| 266 | ch <- i.desc |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | // Collect returns the current state of all metrics of the collector. |
| 271 | func (c *goCollector) Collect(ch chan<- Metric) { |
| 272 | ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine())) |
| 273 | n, _ := runtime.ThreadCreateProfile(nil) |
| 274 | ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n)) |
| 275 | |
| 276 | var stats debug.GCStats |
| 277 | stats.PauseQuantiles = make([]time.Duration, 5) |
| 278 | debug.ReadGCStats(&stats) |
| 279 | |
| 280 | quantiles := make(map[float64]float64) |
| 281 | for idx, pq := range stats.PauseQuantiles[1:] { |
| 282 | quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds() |
| 283 | } |
| 284 | quantiles[0.0] = stats.PauseQuantiles[0].Seconds() |
| 285 | ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles) |
| 286 | |
| 287 | ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1) |
| 288 | |
| 289 | ms := &runtime.MemStats{} |
| 290 | runtime.ReadMemStats(ms) |
| 291 | for _, i := range c.metrics { |
| 292 | ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms)) |
| 293 | } |
| 294 | } |
| 295 | |
| 296 | // memStatsMetrics provide description, value, and value type for memstat metrics. |
| 297 | type memStatsMetrics []struct { |
| 298 | desc *Desc |
| 299 | eval func(*runtime.MemStats) float64 |
| 300 | valType ValueType |
| 301 | } |