src/runtime/metrics/doc.go - go - Git at Google

 // Copyright 2020 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 // Note: run 'go generate' (which will run 'go test -generate') to update the "Supported metrics" list.
 //go:generate go test -run=Docs -generate

 /*
 Package metrics provides a stable interface to access implementation-defined
 metrics exported by the Go runtime. This package is similar to existing functions
 like [runtime.ReadMemStats] and [debug.ReadGCStats], but significantly more general.

 The set of metrics defined by this package may evolve as the runtime itself
 evolves, and also enables variation across Go implementations, whose relevant
 metric sets may not intersect.

 # Interface

 Metrics are designated by a string key, rather than, for example, a field name in
 a struct. The full list of supported metrics is always available in the slice of
 Descriptions returned by All. Each Description also includes useful information
 about the metric.

 Thus, users of this API are encouraged to sample supported metrics defined by the
 slice returned by All to remain compatible across Go versions. Of course, situations
 arise where reading specific metrics is critical. For these cases, users are
 encouraged to use build tags, and although metrics may be deprecated and removed,
 users should consider this to be an exceptional and rare event, coinciding with a
 very large change in a particular Go implementation.

 Each metric key also has a "kind" that describes the format of the metric's value.
 In the interest of not breaking users of this package, the "kind" for a given metric
 is guaranteed not to change. If it must change, then a new metric will be introduced
 with a new key and a new "kind."

 # Metric key format

 As mentioned earlier, metric keys are strings. Their format is simple and well-defined,
 designed to be both human and machine readable. It is split into two components,
 separated by a colon: a rooted path and a unit. The choice to include the unit in
 the key is motivated by compatibility: if a metric's unit changes, its semantics likely
 did also, and a new key should be introduced.

 For more details on the precise definition of the metric key's path and unit formats, see
 the documentation of the Name field of the Description struct.

 # A note about floats

 This package supports metrics whose values have a floating-point representation. In
 order to improve ease-of-use, this package promises to never produce the following
 classes of floating-point values: NaN, infinity.

 # Supported metrics

 Below is the full list of supported metrics, ordered lexicographically.

 	/cgo/go-to-c-calls:calls
 		Count of calls made from Go to C by the current process.

 	/cpu/classes/gc/mark/assist:cpu-seconds
 		Estimated total CPU time goroutines spent performing GC
 		tasks to assist the GC and prevent it from falling behind the
 		application. This metric is an overestimate, and not directly
 		comparable to system CPU time measurements. Compare only with
 		other /cpu/classes metrics.

 	/cpu/classes/gc/mark/dedicated:cpu-seconds
 		Estimated total CPU time spent performing GC tasks on processors
 		(as defined by GOMAXPROCS) dedicated to those tasks. This metric
 		is an overestimate, and not directly comparable to system CPU
 		time measurements. Compare only with other /cpu/classes metrics.

 	/cpu/classes/gc/mark/idle:cpu-seconds
 		Estimated total CPU time spent performing GC tasks on spare CPU
 		resources that the Go scheduler could not otherwise find a use
 		for. This should be subtracted from the total GC CPU time to
 		obtain a measure of compulsory GC CPU time. This metric is an
 		overestimate, and not directly comparable to system CPU time
 		measurements. Compare only with other /cpu/classes metrics.

 	/cpu/classes/gc/pause:cpu-seconds
 		Estimated total CPU time spent with the application paused by
 		the GC. Even if only one thread is running during the pause,
 		this is computed as GOMAXPROCS times the pause latency because
 		nothing else can be executing. This is the exact sum of samples
 		in /gc/pause:seconds if each sample is multiplied by GOMAXPROCS
 		at the time it is taken. This metric is an overestimate,
 		and not directly comparable to system CPU time measurements.
 		Compare only with other /cpu/classes metrics.

 	/cpu/classes/gc/total:cpu-seconds
 		Estimated total CPU time spent performing GC tasks. This metric
 		is an overestimate, and not directly comparable to system CPU
 		time measurements. Compare only with other /cpu/classes metrics.
 		Sum of all metrics in /cpu/classes/gc.

 	/cpu/classes/idle:cpu-seconds
 		Estimated total available CPU time not spent executing
 		any Go or Go runtime code. In other words, the part of
 		/cpu/classes/total:cpu-seconds that was unused. This metric is
 		an overestimate, and not directly comparable to system CPU time
 		measurements. Compare only with other /cpu/classes metrics.

 	/cpu/classes/scavenge/assist:cpu-seconds
 		Estimated total CPU time spent returning unused memory to the
 		underlying platform in response eagerly in response to memory
 		pressure. This metric is an overestimate, and not directly
 		comparable to system CPU time measurements. Compare only with
 		other /cpu/classes metrics.

 	/cpu/classes/scavenge/background:cpu-seconds
 		Estimated total CPU time spent performing background tasks to
 		return unused memory to the underlying platform. This metric is
 		an overestimate, and not directly comparable to system CPU time
 		measurements. Compare only with other /cpu/classes metrics.

 	/cpu/classes/scavenge/total:cpu-seconds
 		Estimated total CPU time spent performing tasks that return
 		unused memory to the underlying platform. This metric is an
 		overestimate, and not directly comparable to system CPU time
 		measurements. Compare only with other /cpu/classes metrics.
 		Sum of all metrics in /cpu/classes/scavenge.

 	/cpu/classes/total:cpu-seconds
 		Estimated total available CPU time for user Go code or the Go
 		runtime, as defined by GOMAXPROCS. In other words, GOMAXPROCS
 		integrated over the wall-clock duration this process has been
 		executing for. This metric is an overestimate, and not directly
 		comparable to system CPU time measurements. Compare only with
 		other /cpu/classes metrics. Sum of all metrics in /cpu/classes.

 	/cpu/classes/user:cpu-seconds
 		Estimated total CPU time spent running user Go code. This may
 		also include some small amount of time spent in the Go runtime.
 		This metric is an overestimate, and not directly comparable
 		to system CPU time measurements. Compare only with other
 		/cpu/classes metrics.

 	/gc/cycles/automatic:gc-cycles
 		Count of completed GC cycles generated by the Go runtime.

 	/gc/cycles/forced:gc-cycles
 		Count of completed GC cycles forced by the application.

 	/gc/cycles/total:gc-cycles
 		Count of all completed GC cycles.

 	/gc/gogc:percent
 		Heap size target percentage configured by the user, otherwise
 		100. This value is set by the GOGC environment variable, and the
 		runtime/debug.SetGCPercent function.

 	/gc/gomemlimit:bytes
 		Go runtime memory limit configured by the user, otherwise
 		math.MaxInt64. This value is set by the GOMEMLIMIT environment
 		variable, and the runtime/debug.SetMemoryLimit function.

 	/gc/heap/allocs-by-size:bytes
 		Distribution of heap allocations by approximate size.
 		Bucket counts increase monotonically. Note that this does not
 		include tiny objects as defined by /gc/heap/tiny/allocs:objects,
 		only tiny blocks.

 	/gc/heap/allocs:bytes
 		Cumulative sum of memory allocated to the heap by the
 		application.

 	/gc/heap/allocs:objects
 		Cumulative count of heap allocations triggered by the
 		application. Note that this does not include tiny objects as
 		defined by /gc/heap/tiny/allocs:objects, only tiny blocks.

 	/gc/heap/frees-by-size:bytes
 		Distribution of freed heap allocations by approximate size.
 		Bucket counts increase monotonically. Note that this does not
 		include tiny objects as defined by /gc/heap/tiny/allocs:objects,
 		only tiny blocks.

 	/gc/heap/frees:bytes
 		Cumulative sum of heap memory freed by the garbage collector.

 	/gc/heap/frees:objects
 		Cumulative count of heap allocations whose storage was freed
 		by the garbage collector. Note that this does not include tiny
 		objects as defined by /gc/heap/tiny/allocs:objects, only tiny
 		blocks.

 	/gc/heap/goal:bytes
 		Heap size target for the end of the GC cycle.

 	/gc/heap/live:bytes
 		Heap memory occupied by live objects that were marked by the
 		previous GC.

 	/gc/heap/objects:objects
 		Number of objects, live or unswept, occupying heap memory.

 	/gc/heap/tiny/allocs:objects
 		Count of small allocations that are packed together into blocks.
 		These allocations are counted separately from other allocations
 		because each individual allocation is not tracked by the
 		runtime, only their block. Each block is already accounted for
 		in allocs-by-size and frees-by-size.

 	/gc/limiter/last-enabled:gc-cycle
 		GC cycle the last time the GC CPU limiter was enabled.
 		This metric is useful for diagnosing the root cause of an
 		out-of-memory error, because the limiter trades memory for CPU
 		time when the GC's CPU time gets too high. This is most likely
 		to occur with use of SetMemoryLimit. The first GC cycle is cycle
 		1, so a value of 0 indicates that it was never enabled.

 	/gc/pauses:seconds
 		Distribution of individual GC-related stop-the-world pause
 		latencies. Bucket counts increase monotonically.

 	/gc/scan/globals:bytes
 		The total amount of global variable space that is scannable.

 	/gc/scan/heap:bytes
 		The total amount of heap space that is scannable.

 	/gc/scan/stack:bytes
 		The number of bytes of stack that were scanned last GC cycle.

 	/gc/scan/total:bytes
 		The total amount space that is scannable. Sum of all metrics in
 		/gc/scan.

 	/gc/stack/starting-size:bytes
 		The stack size of new goroutines.

 	/godebug/non-default-behavior/execerrdot:events
 		The number of non-default behaviors executed by the os/exec
 		package due to a non-default GODEBUG=execerrdot=... setting.

 	/godebug/non-default-behavior/gocachehash:events
 		The number of non-default behaviors executed by the cmd/go
 		package due to a non-default GODEBUG=gocachehash=... setting.

 	/godebug/non-default-behavior/gocachetest:events
 		The number of non-default behaviors executed by the cmd/go
 		package due to a non-default GODEBUG=gocachetest=... setting.

 	/godebug/non-default-behavior/gocacheverify:events
 		The number of non-default behaviors executed by the cmd/go
 		package due to a non-default GODEBUG=gocacheverify=... setting.

 	/godebug/non-default-behavior/http2client:events
 		The number of non-default behaviors executed by the net/http
 		package due to a non-default GODEBUG=http2client=... setting.

 	/godebug/non-default-behavior/http2server:events
 		The number of non-default behaviors executed by the net/http
 		package due to a non-default GODEBUG=http2server=... setting.

 	/godebug/non-default-behavior/installgoroot:events
 		The number of non-default behaviors executed by the go/build
 		package due to a non-default GODEBUG=installgoroot=... setting.

 	/godebug/non-default-behavior/jstmpllitinterp:events
 		The number of non-default behaviors executed by
 		the html/template package due to a non-default
 		GODEBUG=jstmpllitinterp=... setting.

 	/godebug/non-default-behavior/multipartmaxheaders:events
 		The number of non-default behaviors executed by
 		the mime/multipart package due to a non-default
 		GODEBUG=multipartmaxheaders=... setting.

 	/godebug/non-default-behavior/multipartmaxparts:events
 		The number of non-default behaviors executed by
 		the mime/multipart package due to a non-default
 		GODEBUG=multipartmaxparts=... setting.

 	/godebug/non-default-behavior/panicnil:events
 		The number of non-default behaviors executed by the runtime
 		package due to a non-default GODEBUG=panicnil=... setting.

 	/godebug/non-default-behavior/randautoseed:events
 		The number of non-default behaviors executed by the math/rand
 		package due to a non-default GODEBUG=randautoseed=... setting.

 	/godebug/non-default-behavior/tarinsecurepath:events
 		The number of non-default behaviors executed by the archive/tar
 		package due to a non-default GODEBUG=tarinsecurepath=...
 		setting.

 	/godebug/non-default-behavior/x509sha1:events
 		The number of non-default behaviors executed by the crypto/x509
 		package due to a non-default GODEBUG=x509sha1=... setting.

 	/godebug/non-default-behavior/x509usefallbackroots:events
 		The number of non-default behaviors executed by the crypto/x509
 		package due to a non-default GODEBUG=x509usefallbackroots=...
 		setting.

 	/godebug/non-default-behavior/zipinsecurepath:events
 		The number of non-default behaviors executed by the archive/zip
 		package due to a non-default GODEBUG=zipinsecurepath=...
 		setting.

 	/memory/classes/heap/free:bytes
 		Memory that is completely free and eligible to be returned to
 		the underlying system, but has not been. This metric is the
 		runtime's estimate of free address space that is backed by
 		physical memory.

 	/memory/classes/heap/objects:bytes
 		Memory occupied by live objects and dead objects that have not
 		yet been marked free by the garbage collector.

 	/memory/classes/heap/released:bytes
 		Memory that is completely free and has been returned to the
 		underlying system. This metric is the runtime's estimate of free
 		address space that is still mapped into the process, but is not
 		backed by physical memory.

 	/memory/classes/heap/stacks:bytes
 		Memory allocated from the heap that is reserved for stack space,
 		whether or not it is currently in-use. Currently, this
 		represents all stack memory for goroutines. It also includes all
 		OS thread stacks in non-cgo programs. Note that stacks may be
 		allocated differently in the future, and this may change.

 	/memory/classes/heap/unused:bytes
 		Memory that is reserved for heap objects but is not currently
 		used to hold heap objects.

 	/memory/classes/metadata/mcache/free:bytes
 		Memory that is reserved for runtime mcache structures, but not
 		in-use.

 	/memory/classes/metadata/mcache/inuse:bytes
 		Memory that is occupied by runtime mcache structures that are
 		currently being used.

 	/memory/classes/metadata/mspan/free:bytes
 		Memory that is reserved for runtime mspan structures, but not
 		in-use.

 	/memory/classes/metadata/mspan/inuse:bytes
 		Memory that is occupied by runtime mspan structures that are
 		currently being used.

 	/memory/classes/metadata/other:bytes
 		Memory that is reserved for or used to hold runtime metadata.

 	/memory/classes/os-stacks:bytes
 		Stack memory allocated by the underlying operating system.
 		In non-cgo programs this metric is currently zero. This may
 		change in the future.In cgo programs this metric includes
 		OS thread stacks allocated directly from the OS. Currently,
 		this only accounts for one stack in c-shared and c-archive build
 		modes, and other sources of stacks from the OS are not measured.
 		This too may change in the future.

 	/memory/classes/other:bytes
 		Memory used by execution trace buffers, structures for debugging
 		the runtime, finalizer and profiler specials, and more.

 	/memory/classes/profiling/buckets:bytes
 		Memory that is used by the stack trace hash map used for
 		profiling.

 	/memory/classes/total:bytes
 		All memory mapped by the Go runtime into the current process
 		as read-write. Note that this does not include memory mapped
 		by code called via cgo or via the syscall package. Sum of all
 		metrics in /memory/classes.

 	/sched/gomaxprocs:threads
 		The current runtime.GOMAXPROCS setting, or the number of
 		operating system threads that can execute user-level Go code
 		simultaneously.

 	/sched/goroutines:goroutines
 		Count of live goroutines.

 	/sched/latencies:seconds
 		Distribution of the time goroutines have spent in the scheduler
 		in a runnable state before actually running. Bucket counts
 		increase monotonically.

 	/sync/mutex/wait/total:seconds
 		Approximate cumulative time goroutines have spent blocked
 		on a sync.Mutex or sync.RWMutex. This metric is useful for
 		identifying global changes in lock contention. Collect a mutex
 		or block profile using the runtime/pprof package for more
 		detailed contention data.
 */
 package metrics
	// Copyright 2020 The Go Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	// Note: run 'go generate' (which will run 'go test -generate') to update the "Supported metrics" list.
	//go:generate go test -run=Docs -generate

	/*
	Package metrics provides a stable interface to access implementation-defined
	metrics exported by the Go runtime. This package is similar to existing functions
	like [runtime.ReadMemStats] and [debug.ReadGCStats], but significantly more general.

	The set of metrics defined by this package may evolve as the runtime itself
	evolves, and also enables variation across Go implementations, whose relevant
	metric sets may not intersect.

	# Interface

	Metrics are designated by a string key, rather than, for example, a field name in
	a struct. The full list of supported metrics is always available in the slice of
	Descriptions returned by All. Each Description also includes useful information
	about the metric.

	Thus, users of this API are encouraged to sample supported metrics defined by the
	slice returned by All to remain compatible across Go versions. Of course, situations
	arise where reading specific metrics is critical. For these cases, users are
	encouraged to use build tags, and although metrics may be deprecated and removed,
	users should consider this to be an exceptional and rare event, coinciding with a
	very large change in a particular Go implementation.

	Each metric key also has a "kind" that describes the format of the metric's value.
	In the interest of not breaking users of this package, the "kind" for a given metric
	is guaranteed not to change. If it must change, then a new metric will be introduced
	with a new key and a new "kind."

	# Metric key format

	As mentioned earlier, metric keys are strings. Their format is simple and well-defined,
	designed to be both human and machine readable. It is split into two components,
	separated by a colon: a rooted path and a unit. The choice to include the unit in
	the key is motivated by compatibility: if a metric's unit changes, its semantics likely
	did also, and a new key should be introduced.

	For more details on the precise definition of the metric key's path and unit formats, see
	the documentation of the Name field of the Description struct.

	# A note about floats

	This package supports metrics whose values have a floating-point representation. In
	order to improve ease-of-use, this package promises to never produce the following
	classes of floating-point values: NaN, infinity.

	# Supported metrics

	Below is the full list of supported metrics, ordered lexicographically.

	/cgo/go-to-c-calls:calls
	Count of calls made from Go to C by the current process.

	/cpu/classes/gc/mark/assist:cpu-seconds
	Estimated total CPU time goroutines spent performing GC
	tasks to assist the GC and prevent it from falling behind the
	application. This metric is an overestimate, and not directly
	comparable to system CPU time measurements. Compare only with
	other /cpu/classes metrics.

	/cpu/classes/gc/mark/dedicated:cpu-seconds
	Estimated total CPU time spent performing GC tasks on processors
	(as defined by GOMAXPROCS) dedicated to those tasks. This metric
	is an overestimate, and not directly comparable to system CPU
	time measurements. Compare only with other /cpu/classes metrics.

	/cpu/classes/gc/mark/idle:cpu-seconds
	Estimated total CPU time spent performing GC tasks on spare CPU
	resources that the Go scheduler could not otherwise find a use
	for. This should be subtracted from the total GC CPU time to
	obtain a measure of compulsory GC CPU time. This metric is an
	overestimate, and not directly comparable to system CPU time
	measurements. Compare only with other /cpu/classes metrics.

	/cpu/classes/gc/pause:cpu-seconds
	Estimated total CPU time spent with the application paused by
	the GC. Even if only one thread is running during the pause,
	this is computed as GOMAXPROCS times the pause latency because
	nothing else can be executing. This is the exact sum of samples
	in /gc/pause:seconds if each sample is multiplied by GOMAXPROCS
	at the time it is taken. This metric is an overestimate,
	and not directly comparable to system CPU time measurements.
	Compare only with other /cpu/classes metrics.

	/cpu/classes/gc/total:cpu-seconds
	Estimated total CPU time spent performing GC tasks. This metric
	is an overestimate, and not directly comparable to system CPU
	time measurements. Compare only with other /cpu/classes metrics.
	Sum of all metrics in /cpu/classes/gc.

	/cpu/classes/idle:cpu-seconds
	Estimated total available CPU time not spent executing
	any Go or Go runtime code. In other words, the part of
	/cpu/classes/total:cpu-seconds that was unused. This metric is
	an overestimate, and not directly comparable to system CPU time
	measurements. Compare only with other /cpu/classes metrics.

	/cpu/classes/scavenge/assist:cpu-seconds
	Estimated total CPU time spent returning unused memory to the
	underlying platform in response eagerly in response to memory
	pressure. This metric is an overestimate, and not directly
	comparable to system CPU time measurements. Compare only with
	other /cpu/classes metrics.

	/cpu/classes/scavenge/background:cpu-seconds
	Estimated total CPU time spent performing background tasks to
	return unused memory to the underlying platform. This metric is
	an overestimate, and not directly comparable to system CPU time
	measurements. Compare only with other /cpu/classes metrics.

	/cpu/classes/scavenge/total:cpu-seconds
	Estimated total CPU time spent performing tasks that return
	unused memory to the underlying platform. This metric is an
	overestimate, and not directly comparable to system CPU time
	measurements. Compare only with other /cpu/classes metrics.
	Sum of all metrics in /cpu/classes/scavenge.

	/cpu/classes/total:cpu-seconds
	Estimated total available CPU time for user Go code or the Go
	runtime, as defined by GOMAXPROCS. In other words, GOMAXPROCS
	integrated over the wall-clock duration this process has been
	executing for. This metric is an overestimate, and not directly
	comparable to system CPU time measurements. Compare only with
	other /cpu/classes metrics. Sum of all metrics in /cpu/classes.

	/cpu/classes/user:cpu-seconds
	Estimated total CPU time spent running user Go code. This may
	also include some small amount of time spent in the Go runtime.
	This metric is an overestimate, and not directly comparable
	to system CPU time measurements. Compare only with other
	/cpu/classes metrics.

	/gc/cycles/automatic:gc-cycles
	Count of completed GC cycles generated by the Go runtime.

	/gc/cycles/forced:gc-cycles
	Count of completed GC cycles forced by the application.

	/gc/cycles/total:gc-cycles
	Count of all completed GC cycles.

	/gc/gogc:percent
	Heap size target percentage configured by the user, otherwise
	100. This value is set by the GOGC environment variable, and the
	runtime/debug.SetGCPercent function.

	/gc/gomemlimit:bytes
	Go runtime memory limit configured by the user, otherwise
	math.MaxInt64. This value is set by the GOMEMLIMIT environment
	variable, and the runtime/debug.SetMemoryLimit function.

	/gc/heap/allocs-by-size:bytes
	Distribution of heap allocations by approximate size.
	Bucket counts increase monotonically. Note that this does not
	include tiny objects as defined by /gc/heap/tiny/allocs:objects,
	only tiny blocks.

	/gc/heap/allocs:bytes
	Cumulative sum of memory allocated to the heap by the
	application.

	/gc/heap/allocs:objects
	Cumulative count of heap allocations triggered by the
	application. Note that this does not include tiny objects as
	defined by /gc/heap/tiny/allocs:objects, only tiny blocks.

	/gc/heap/frees-by-size:bytes
	Distribution of freed heap allocations by approximate size.
	Bucket counts increase monotonically. Note that this does not
	include tiny objects as defined by /gc/heap/tiny/allocs:objects,
	only tiny blocks.

	/gc/heap/frees:bytes
	Cumulative sum of heap memory freed by the garbage collector.

	/gc/heap/frees:objects
	Cumulative count of heap allocations whose storage was freed
	by the garbage collector. Note that this does not include tiny
	objects as defined by /gc/heap/tiny/allocs:objects, only tiny
	blocks.

	/gc/heap/goal:bytes
	Heap size target for the end of the GC cycle.

	/gc/heap/live:bytes
	Heap memory occupied by live objects that were marked by the
	previous GC.

	/gc/heap/objects:objects
	Number of objects, live or unswept, occupying heap memory.

	/gc/heap/tiny/allocs:objects
	Count of small allocations that are packed together into blocks.
	These allocations are counted separately from other allocations
	because each individual allocation is not tracked by the
	runtime, only their block. Each block is already accounted for
	in allocs-by-size and frees-by-size.

	/gc/limiter/last-enabled:gc-cycle
	GC cycle the last time the GC CPU limiter was enabled.
	This metric is useful for diagnosing the root cause of an
	out-of-memory error, because the limiter trades memory for CPU
	time when the GC's CPU time gets too high. This is most likely
	to occur with use of SetMemoryLimit. The first GC cycle is cycle
	1, so a value of 0 indicates that it was never enabled.

	/gc/pauses:seconds
	Distribution of individual GC-related stop-the-world pause
	latencies. Bucket counts increase monotonically.

	/gc/scan/globals:bytes
	The total amount of global variable space that is scannable.

	/gc/scan/heap:bytes
	The total amount of heap space that is scannable.

	/gc/scan/stack:bytes
	The number of bytes of stack that were scanned last GC cycle.

	/gc/scan/total:bytes
	The total amount space that is scannable. Sum of all metrics in
	/gc/scan.

	/gc/stack/starting-size:bytes
	The stack size of new goroutines.

	/godebug/non-default-behavior/execerrdot:events
	The number of non-default behaviors executed by the os/exec
	package due to a non-default GODEBUG=execerrdot=... setting.

	/godebug/non-default-behavior/gocachehash:events
	The number of non-default behaviors executed by the cmd/go
	package due to a non-default GODEBUG=gocachehash=... setting.

	/godebug/non-default-behavior/gocachetest:events
	The number of non-default behaviors executed by the cmd/go
	package due to a non-default GODEBUG=gocachetest=... setting.

	/godebug/non-default-behavior/gocacheverify:events
	The number of non-default behaviors executed by the cmd/go
	package due to a non-default GODEBUG=gocacheverify=... setting.

	/godebug/non-default-behavior/http2client:events
	The number of non-default behaviors executed by the net/http
	package due to a non-default GODEBUG=http2client=... setting.

	/godebug/non-default-behavior/http2server:events
	The number of non-default behaviors executed by the net/http
	package due to a non-default GODEBUG=http2server=... setting.

	/godebug/non-default-behavior/installgoroot:events
	The number of non-default behaviors executed by the go/build
	package due to a non-default GODEBUG=installgoroot=... setting.

	/godebug/non-default-behavior/jstmpllitinterp:events
	The number of non-default behaviors executed by
	the html/template package due to a non-default
	GODEBUG=jstmpllitinterp=... setting.

	/godebug/non-default-behavior/multipartmaxheaders:events
	The number of non-default behaviors executed by
	the mime/multipart package due to a non-default
	GODEBUG=multipartmaxheaders=... setting.

	/godebug/non-default-behavior/multipartmaxparts:events
	The number of non-default behaviors executed by
	the mime/multipart package due to a non-default
	GODEBUG=multipartmaxparts=... setting.

	/godebug/non-default-behavior/panicnil:events
	The number of non-default behaviors executed by the runtime
	package due to a non-default GODEBUG=panicnil=... setting.

	/godebug/non-default-behavior/randautoseed:events
	The number of non-default behaviors executed by the math/rand
	package due to a non-default GODEBUG=randautoseed=... setting.

	/godebug/non-default-behavior/tarinsecurepath:events
	The number of non-default behaviors executed by the archive/tar
	package due to a non-default GODEBUG=tarinsecurepath=...
	setting.

	/godebug/non-default-behavior/x509sha1:events
	The number of non-default behaviors executed by the crypto/x509
	package due to a non-default GODEBUG=x509sha1=... setting.

	/godebug/non-default-behavior/x509usefallbackroots:events
	The number of non-default behaviors executed by the crypto/x509
	package due to a non-default GODEBUG=x509usefallbackroots=...
	setting.

	/godebug/non-default-behavior/zipinsecurepath:events
	The number of non-default behaviors executed by the archive/zip
	package due to a non-default GODEBUG=zipinsecurepath=...
	setting.

	/memory/classes/heap/free:bytes
	Memory that is completely free and eligible to be returned to
	the underlying system, but has not been. This metric is the
	runtime's estimate of free address space that is backed by
	physical memory.

	/memory/classes/heap/objects:bytes
	Memory occupied by live objects and dead objects that have not
	yet been marked free by the garbage collector.

	/memory/classes/heap/released:bytes
	Memory that is completely free and has been returned to the
	underlying system. This metric is the runtime's estimate of free
	address space that is still mapped into the process, but is not
	backed by physical memory.

	/memory/classes/heap/stacks:bytes
	Memory allocated from the heap that is reserved for stack space,
	whether or not it is currently in-use. Currently, this
	represents all stack memory for goroutines. It also includes all
	OS thread stacks in non-cgo programs. Note that stacks may be
	allocated differently in the future, and this may change.

	/memory/classes/heap/unused:bytes
	Memory that is reserved for heap objects but is not currently
	used to hold heap objects.

	/memory/classes/metadata/mcache/free:bytes
	Memory that is reserved for runtime mcache structures, but not
	in-use.

	/memory/classes/metadata/mcache/inuse:bytes
	Memory that is occupied by runtime mcache structures that are
	currently being used.

	/memory/classes/metadata/mspan/free:bytes
	Memory that is reserved for runtime mspan structures, but not
	in-use.

	/memory/classes/metadata/mspan/inuse:bytes
	Memory that is occupied by runtime mspan structures that are
	currently being used.

	/memory/classes/metadata/other:bytes
	Memory that is reserved for or used to hold runtime metadata.

	/memory/classes/os-stacks:bytes
	Stack memory allocated by the underlying operating system.
	In non-cgo programs this metric is currently zero. This may
	change in the future.In cgo programs this metric includes
	OS thread stacks allocated directly from the OS. Currently,
	this only accounts for one stack in c-shared and c-archive build
	modes, and other sources of stacks from the OS are not measured.
	This too may change in the future.

	/memory/classes/other:bytes
	Memory used by execution trace buffers, structures for debugging
	the runtime, finalizer and profiler specials, and more.

	/memory/classes/profiling/buckets:bytes
	Memory that is used by the stack trace hash map used for
	profiling.

	/memory/classes/total:bytes
	All memory mapped by the Go runtime into the current process
	as read-write. Note that this does not include memory mapped
	by code called via cgo or via the syscall package. Sum of all
	metrics in /memory/classes.

	/sched/gomaxprocs:threads
	The current runtime.GOMAXPROCS setting, or the number of
	operating system threads that can execute user-level Go code
	simultaneously.

	/sched/goroutines:goroutines
	Count of live goroutines.

	/sched/latencies:seconds
	Distribution of the time goroutines have spent in the scheduler
	in a runnable state before actually running. Bucket counts
	increase monotonically.

	/sync/mutex/wait/total:seconds
	Approximate cumulative time goroutines have spent blocked
	on a sync.Mutex or sync.RWMutex. This metric is useful for
	identifying global changes in lock contention. Collect a mutex
	or block profile using the runtime/pprof package for more
	detailed contention data.
	*/
	package metrics