Source file src/runtime/metrics/doc.go

     1  // Copyright 2020 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Note: run 'go generate' (which will run 'go test -generate') to update the "Supported metrics" list.
     6  //go:generate go test -run=Docs -generate
     7  
     8  /*
     9  Package metrics provides a stable interface to access implementation-defined
    10  metrics exported by the Go runtime. This package is similar to existing functions
    11  like [runtime.ReadMemStats] and [runtime/debug.ReadGCStats], but significantly more general.
    12  
    13  The set of metrics defined by this package may evolve as the runtime itself
    14  evolves, and also enables variation across Go implementations, whose relevant
    15  metric sets may not intersect.
    16  
    17  # Interface
    18  
    19  Metrics are designated by a string key, rather than, for example, a field name in
    20  a struct. The full list of supported metrics is always available in the slice of
    21  Descriptions returned by [All]. Each [Description] also includes useful information
    22  about the metric.
    23  
    24  Thus, users of this API are encouraged to sample supported metrics defined by the
    25  slice returned by All to remain compatible across Go versions. Of course, situations
    26  arise where reading specific metrics is critical. For these cases, users are
    27  encouraged to use build tags, and although metrics may be deprecated and removed,
    28  users should consider this to be an exceptional and rare event, coinciding with a
    29  very large change in a particular Go implementation.
    30  
    31  Each metric key also has a "kind" (see [ValueKind]) that describes the format of the
    32  metric's value.
    33  In the interest of not breaking users of this package, the "kind" for a given metric
    34  is guaranteed not to change. If it must change, then a new metric will be introduced
    35  with a new key and a new "kind."
    36  
    37  # Metric key format
    38  
    39  As mentioned earlier, metric keys are strings. Their format is simple and well-defined,
    40  designed to be both human and machine readable. It is split into two components,
    41  separated by a colon: a rooted path and a unit. The choice to include the unit in
    42  the key is motivated by compatibility: if a metric's unit changes, its semantics likely
    43  did also, and a new key should be introduced.
    44  
    45  For more details on the precise definition of the metric key's path and unit formats, see
    46  the documentation of the Name field of the Description struct.
    47  
    48  # A note about floats
    49  
    50  This package supports metrics whose values have a floating-point representation. In
    51  order to improve ease-of-use, this package promises to never produce the following
    52  classes of floating-point values: NaN, infinity.
    53  
    54  # Supported metrics
    55  
    56  Below is the full list of supported metrics, ordered lexicographically.
    57  
    58  	/cgo/go-to-c-calls:calls
    59  		Count of calls made from Go to C by the current process.
    60  
    61  	/cpu/classes/gc/mark/assist:cpu-seconds
    62  		Estimated total CPU time goroutines spent performing GC
    63  		tasks to assist the GC and prevent it from falling behind the
    64  		application. This metric is an overestimate, and not directly
    65  		comparable to system CPU time measurements. Compare only with
    66  		other /cpu/classes metrics.
    67  
    68  	/cpu/classes/gc/mark/dedicated:cpu-seconds
    69  		Estimated total CPU time spent performing GC tasks on processors
    70  		(as defined by GOMAXPROCS) dedicated to those tasks. This metric
    71  		is an overestimate, and not directly comparable to system CPU
    72  		time measurements. Compare only with other /cpu/classes metrics.
    73  
    74  	/cpu/classes/gc/mark/idle:cpu-seconds
    75  		Estimated total CPU time spent performing GC tasks on spare CPU
    76  		resources that the Go scheduler could not otherwise find a use
    77  		for. This should be subtracted from the total GC CPU time to
    78  		obtain a measure of compulsory GC CPU time. This metric is an
    79  		overestimate, and not directly comparable to system CPU time
    80  		measurements. Compare only with other /cpu/classes metrics.
    81  
    82  	/cpu/classes/gc/pause:cpu-seconds
    83  		Estimated total CPU time spent with the application paused by
    84  		the GC. Even if only one thread is running during the pause,
    85  		this is computed as GOMAXPROCS times the pause latency because
    86  		nothing else can be executing. This is the exact sum of samples
    87  		in /sched/pauses/total/gc:seconds if each sample is multiplied
    88  		by GOMAXPROCS at the time it is taken. This metric is an
    89  		overestimate, and not directly comparable to system CPU time
    90  		measurements. Compare only with other /cpu/classes metrics.
    91  
    92  	/cpu/classes/gc/total:cpu-seconds
    93  		Estimated total CPU time spent performing GC tasks. This metric
    94  		is an overestimate, and not directly comparable to system CPU
    95  		time measurements. Compare only with other /cpu/classes metrics.
    96  		Sum of all metrics in /cpu/classes/gc.
    97  
    98  	/cpu/classes/idle:cpu-seconds
    99  		Estimated total available CPU time not spent executing
   100  		any Go or Go runtime code. In other words, the part of
   101  		/cpu/classes/total:cpu-seconds that was unused. This metric is
   102  		an overestimate, and not directly comparable to system CPU time
   103  		measurements. Compare only with other /cpu/classes metrics.
   104  
   105  	/cpu/classes/scavenge/assist:cpu-seconds
   106  		Estimated total CPU time spent returning unused memory to the
   107  		underlying platform in response eagerly to memory pressure. This
   108  		metric is an overestimate, and not directly comparable to system
   109  		CPU time measurements. Compare only with other /cpu/classes
   110  		metrics.
   111  
   112  	/cpu/classes/scavenge/background:cpu-seconds
   113  		Estimated total CPU time spent performing background tasks to
   114  		return unused memory to the underlying platform. This metric is
   115  		an overestimate, and not directly comparable to system CPU time
   116  		measurements. Compare only with other /cpu/classes metrics.
   117  
   118  	/cpu/classes/scavenge/total:cpu-seconds
   119  		Estimated total CPU time spent performing tasks that return
   120  		unused memory to the underlying platform. This metric is an
   121  		overestimate, and not directly comparable to system CPU time
   122  		measurements. Compare only with other /cpu/classes metrics.
   123  		Sum of all metrics in /cpu/classes/scavenge.
   124  
   125  	/cpu/classes/total:cpu-seconds
   126  		Estimated total available CPU time for user Go code or the Go
   127  		runtime, as defined by GOMAXPROCS. In other words, GOMAXPROCS
   128  		integrated over the wall-clock duration this process has been
   129  		executing for. This metric is an overestimate, and not directly
   130  		comparable to system CPU time measurements. Compare only with
   131  		other /cpu/classes metrics. Sum of all metrics in /cpu/classes.
   132  
   133  	/cpu/classes/user:cpu-seconds
   134  		Estimated total CPU time spent running user Go code. This may
   135  		also include some small amount of time spent in the Go runtime.
   136  		This metric is an overestimate, and not directly comparable
   137  		to system CPU time measurements. Compare only with other
   138  		/cpu/classes metrics.
   139  
   140  	/gc/cleanups/executed:cleanups
   141  		Approximate total count of cleanup functions (created
   142  		by runtime.AddCleanup) executed by the runtime. Subtract
   143  		/gc/cleanups/queued:cleanups to approximate cleanup queue
   144  		length. Useful for detecting slow cleanups holding up the queue.
   145  
   146  	/gc/cleanups/queued:cleanups
   147  		Approximate total count of cleanup functions (created by
   148  		runtime.AddCleanup) queued by the runtime for execution.
   149  		Subtract from /gc/cleanups/executed:cleanups to approximate
   150  		cleanup queue length. Useful for detecting slow cleanups holding
   151  		up the queue.
   152  
   153  	/gc/cycles/automatic:gc-cycles
   154  		Count of completed GC cycles generated by the Go runtime.
   155  
   156  	/gc/cycles/forced:gc-cycles
   157  		Count of completed GC cycles forced by the application.
   158  
   159  	/gc/cycles/total:gc-cycles
   160  		Count of all completed GC cycles.
   161  
   162  	/gc/finalizers/executed:finalizers
   163  		Total count of finalizer functions (created by
   164  		runtime.SetFinalizer) executed by the runtime. Subtract
   165  		/gc/finalizers/queued:finalizers to approximate finalizer queue
   166  		length. Useful for detecting finalizers overwhelming the queue,
   167  		either by being too slow, or by there being too many of them.
   168  
   169  	/gc/finalizers/queued:finalizers
   170  		Total count of finalizer functions (created by
   171  		runtime.SetFinalizer) and queued by the runtime for execution.
   172  		Subtract from /gc/finalizers/executed:finalizers to approximate
   173  		finalizer queue length. Useful for detecting slow finalizers
   174  		holding up the queue.
   175  
   176  	/gc/gogc:percent
   177  		Heap size target percentage configured by the user, otherwise
   178  		100. This value is set by the GOGC environment variable, and the
   179  		runtime/debug.SetGCPercent function.
   180  
   181  	/gc/gomemlimit:bytes
   182  		Go runtime memory limit configured by the user, otherwise
   183  		math.MaxInt64. This value is set by the GOMEMLIMIT environment
   184  		variable, and the runtime/debug.SetMemoryLimit function.
   185  
   186  	/gc/heap/allocs-by-size:bytes
   187  		Distribution of heap allocations by approximate size.
   188  		Bucket counts increase monotonically. Note that this does not
   189  		include tiny objects as defined by /gc/heap/tiny/allocs:objects,
   190  		only tiny blocks.
   191  
   192  	/gc/heap/allocs:bytes
   193  		Cumulative sum of memory allocated to the heap by the
   194  		application.
   195  
   196  	/gc/heap/allocs:objects
   197  		Cumulative count of heap allocations triggered by the
   198  		application. Note that this does not include tiny objects as
   199  		defined by /gc/heap/tiny/allocs:objects, only tiny blocks.
   200  
   201  	/gc/heap/frees-by-size:bytes
   202  		Distribution of freed heap allocations by approximate size.
   203  		Bucket counts increase monotonically. Note that this does not
   204  		include tiny objects as defined by /gc/heap/tiny/allocs:objects,
   205  		only tiny blocks.
   206  
   207  	/gc/heap/frees:bytes
   208  		Cumulative sum of heap memory freed by the garbage collector.
   209  
   210  	/gc/heap/frees:objects
   211  		Cumulative count of heap allocations whose storage was freed
   212  		by the garbage collector. Note that this does not include tiny
   213  		objects as defined by /gc/heap/tiny/allocs:objects, only tiny
   214  		blocks.
   215  
   216  	/gc/heap/goal:bytes
   217  		Heap size target for the end of the GC cycle.
   218  
   219  	/gc/heap/live:bytes
   220  		Heap memory occupied by live objects that were marked by the
   221  		previous GC.
   222  
   223  	/gc/heap/objects:objects
   224  		Number of objects, live or unswept, occupying heap memory.
   225  
   226  	/gc/heap/tiny/allocs:objects
   227  		Count of small allocations that are packed together into blocks.
   228  		These allocations are counted separately from other allocations
   229  		because each individual allocation is not tracked by the
   230  		runtime, only their block. Each block is already accounted for
   231  		in allocs-by-size and frees-by-size.
   232  
   233  	/gc/limiter/last-enabled:gc-cycle
   234  		GC cycle the last time the GC CPU limiter was enabled.
   235  		This metric is useful for diagnosing the root cause of an
   236  		out-of-memory error, because the limiter trades memory for CPU
   237  		time when the GC's CPU time gets too high. This is most likely
   238  		to occur with use of SetMemoryLimit. The first GC cycle is cycle
   239  		1, so a value of 0 indicates that it was never enabled.
   240  
   241  	/gc/pauses:seconds
   242  		Deprecated. Prefer the identical /sched/pauses/total/gc:seconds.
   243  
   244  	/gc/scan/globals:bytes
   245  		The total amount of global variable space that is scannable.
   246  
   247  	/gc/scan/heap:bytes
   248  		The total amount of heap space that is scannable.
   249  
   250  	/gc/scan/stack:bytes
   251  		The number of bytes of stack that were scanned last GC cycle.
   252  
   253  	/gc/scan/total:bytes
   254  		The total amount space that is scannable. Sum of all metrics in
   255  		/gc/scan.
   256  
   257  	/gc/stack/starting-size:bytes
   258  		The stack size of new goroutines.
   259  
   260  	/godebug/non-default-behavior/allowmultiplevcs:events
   261  		The number of non-default behaviors executed by the cmd/go
   262  		package due to a non-default GODEBUG=allowmultiplevcs=...
   263  		setting.
   264  
   265  	/godebug/non-default-behavior/asynctimerchan:events
   266  		The number of non-default behaviors executed by the time package
   267  		due to a non-default GODEBUG=asynctimerchan=... setting.
   268  
   269  	/godebug/non-default-behavior/containermaxprocs:events
   270  		The number of non-default behaviors executed by the runtime
   271  		package due to a non-default GODEBUG=containermaxprocs=...
   272  		setting.
   273  
   274  	/godebug/non-default-behavior/cryptocustomrand:events
   275  		The number of non-default behaviors executed by the crypto
   276  		package due to a non-default GODEBUG=cryptocustomrand=...
   277  		setting.
   278  
   279  	/godebug/non-default-behavior/embedfollowsymlinks:events
   280  		The number of non-default behaviors executed by the cmd/go
   281  		package due to a non-default GODEBUG=embedfollowsymlinks=...
   282  		setting.
   283  
   284  	/godebug/non-default-behavior/execerrdot:events
   285  		The number of non-default behaviors executed by the os/exec
   286  		package due to a non-default GODEBUG=execerrdot=... setting.
   287  
   288  	/godebug/non-default-behavior/fips140ems:events
   289  		The number of non-default behaviors executed by the crypto/tls
   290  		package due to a non-default GODEBUG=fips140ems=... setting.
   291  
   292  	/godebug/non-default-behavior/gocachehash:events
   293  		The number of non-default behaviors executed by the cmd/go
   294  		package due to a non-default GODEBUG=gocachehash=... setting.
   295  
   296  	/godebug/non-default-behavior/gocachetest:events
   297  		The number of non-default behaviors executed by the cmd/go
   298  		package due to a non-default GODEBUG=gocachetest=... setting.
   299  
   300  	/godebug/non-default-behavior/gocacheverify:events
   301  		The number of non-default behaviors executed by the cmd/go
   302  		package due to a non-default GODEBUG=gocacheverify=... setting.
   303  
   304  	/godebug/non-default-behavior/gotestjsonbuildtext:events
   305  		The number of non-default behaviors executed by the cmd/go
   306  		package due to a non-default GODEBUG=gotestjsonbuildtext=...
   307  		setting.
   308  
   309  	/godebug/non-default-behavior/gotypesalias:events
   310  		The number of non-default behaviors executed by the go/types
   311  		package due to a non-default GODEBUG=gotypesalias=... setting.
   312  
   313  	/godebug/non-default-behavior/htmlmetacontenturlescape:events
   314  		The number of non-default behaviors executed by
   315  		the html/template package due to a non-default
   316  		GODEBUG=htmlmetacontenturlescape=... setting.
   317  
   318  	/godebug/non-default-behavior/http2client:events
   319  		The number of non-default behaviors executed by the net/http
   320  		package due to a non-default GODEBUG=http2client=... setting.
   321  
   322  	/godebug/non-default-behavior/http2server:events
   323  		The number of non-default behaviors executed by the net/http
   324  		package due to a non-default GODEBUG=http2server=... setting.
   325  
   326  	/godebug/non-default-behavior/httpcookiemaxnum:events
   327  		The number of non-default behaviors executed by the net/http
   328  		package due to a non-default GODEBUG=httpcookiemaxnum=...
   329  		setting.
   330  
   331  	/godebug/non-default-behavior/httplaxcontentlength:events
   332  		The number of non-default behaviors executed by the net/http
   333  		package due to a non-default GODEBUG=httplaxcontentlength=...
   334  		setting.
   335  
   336  	/godebug/non-default-behavior/httpmuxgo121:events
   337  		The number of non-default behaviors executed by the net/http
   338  		package due to a non-default GODEBUG=httpmuxgo121=... setting.
   339  
   340  	/godebug/non-default-behavior/httpservecontentkeepheaders:events
   341  		The number of non-default behaviors executed
   342  		by the net/http package due to a non-default
   343  		GODEBUG=httpservecontentkeepheaders=... setting.
   344  
   345  	/godebug/non-default-behavior/installgoroot:events
   346  		The number of non-default behaviors executed by the go/build
   347  		package due to a non-default GODEBUG=installgoroot=... setting.
   348  
   349  	/godebug/non-default-behavior/multipartmaxheaders:events
   350  		The number of non-default behaviors executed by
   351  		the mime/multipart package due to a non-default
   352  		GODEBUG=multipartmaxheaders=... setting.
   353  
   354  	/godebug/non-default-behavior/multipartmaxparts:events
   355  		The number of non-default behaviors executed by
   356  		the mime/multipart package due to a non-default
   357  		GODEBUG=multipartmaxparts=... setting.
   358  
   359  	/godebug/non-default-behavior/multipathtcp:events
   360  		The number of non-default behaviors executed by the net package
   361  		due to a non-default GODEBUG=multipathtcp=... setting.
   362  
   363  	/godebug/non-default-behavior/netedns0:events
   364  		The number of non-default behaviors executed by the net package
   365  		due to a non-default GODEBUG=netedns0=... setting.
   366  
   367  	/godebug/non-default-behavior/panicnil:events
   368  		The number of non-default behaviors executed by the runtime
   369  		package due to a non-default GODEBUG=panicnil=... setting.
   370  
   371  	/godebug/non-default-behavior/randautoseed:events
   372  		The number of non-default behaviors executed by the math/rand
   373  		package due to a non-default GODEBUG=randautoseed=... setting.
   374  
   375  	/godebug/non-default-behavior/randseednop:events
   376  		The number of non-default behaviors executed by the math/rand
   377  		package due to a non-default GODEBUG=randseednop=... setting.
   378  
   379  	/godebug/non-default-behavior/rsa1024min:events
   380  		The number of non-default behaviors executed by the crypto/rsa
   381  		package due to a non-default GODEBUG=rsa1024min=... setting.
   382  
   383  	/godebug/non-default-behavior/tarinsecurepath:events
   384  		The number of non-default behaviors executed by the archive/tar
   385  		package due to a non-default GODEBUG=tarinsecurepath=...
   386  		setting.
   387  
   388  	/godebug/non-default-behavior/tls10server:events
   389  		The number of non-default behaviors executed by the crypto/tls
   390  		package due to a non-default GODEBUG=tls10server=... setting.
   391  
   392  	/godebug/non-default-behavior/tls3des:events
   393  		The number of non-default behaviors executed by the crypto/tls
   394  		package due to a non-default GODEBUG=tls3des=... setting.
   395  
   396  	/godebug/non-default-behavior/tlsmaxrsasize:events
   397  		The number of non-default behaviors executed by the crypto/tls
   398  		package due to a non-default GODEBUG=tlsmaxrsasize=... setting.
   399  
   400  	/godebug/non-default-behavior/tlsrsakex:events
   401  		The number of non-default behaviors executed by the crypto/tls
   402  		package due to a non-default GODEBUG=tlsrsakex=... setting.
   403  
   404  	/godebug/non-default-behavior/tlssha1:events
   405  		The number of non-default behaviors executed by the crypto/tls
   406  		package due to a non-default GODEBUG=tlssha1=... setting.
   407  
   408  	/godebug/non-default-behavior/tlsunsafeekm:events
   409  		The number of non-default behaviors executed by the crypto/tls
   410  		package due to a non-default GODEBUG=tlsunsafeekm=... setting.
   411  
   412  	/godebug/non-default-behavior/updatemaxprocs:events
   413  		The number of non-default behaviors executed by the runtime
   414  		package due to a non-default GODEBUG=updatemaxprocs=... setting.
   415  
   416  	/godebug/non-default-behavior/urlmaxqueryparams:events
   417  		The number of non-default behaviors executed by the net/url
   418  		package due to a non-default GODEBUG=urlmaxqueryparams=...
   419  		setting.
   420  
   421  	/godebug/non-default-behavior/urlstrictcolons:events
   422  		The number of non-default behaviors executed by the net/url
   423  		package due to a non-default GODEBUG=urlstrictcolons=...
   424  		setting.
   425  
   426  	/godebug/non-default-behavior/winreadlinkvolume:events
   427  		The number of non-default behaviors executed by the os package
   428  		due to a non-default GODEBUG=winreadlinkvolume=... setting.
   429  
   430  	/godebug/non-default-behavior/winsymlink:events
   431  		The number of non-default behaviors executed by the os package
   432  		due to a non-default GODEBUG=winsymlink=... setting.
   433  
   434  	/godebug/non-default-behavior/x509keypairleaf:events
   435  		The number of non-default behaviors executed by the crypto/tls
   436  		package due to a non-default GODEBUG=x509keypairleaf=...
   437  		setting.
   438  
   439  	/godebug/non-default-behavior/x509negativeserial:events
   440  		The number of non-default behaviors executed by the crypto/x509
   441  		package due to a non-default GODEBUG=x509negativeserial=...
   442  		setting.
   443  
   444  	/godebug/non-default-behavior/x509rsacrt:events
   445  		The number of non-default behaviors executed by the crypto/x509
   446  		package due to a non-default GODEBUG=x509rsacrt=... setting.
   447  
   448  	/godebug/non-default-behavior/x509sha256skid:events
   449  		The number of non-default behaviors executed by the crypto/x509
   450  		package due to a non-default GODEBUG=x509sha256skid=... setting.
   451  
   452  	/godebug/non-default-behavior/x509usefallbackroots:events
   453  		The number of non-default behaviors executed by the crypto/x509
   454  		package due to a non-default GODEBUG=x509usefallbackroots=...
   455  		setting.
   456  
   457  	/godebug/non-default-behavior/x509usepolicies:events
   458  		The number of non-default behaviors executed by the crypto/x509
   459  		package due to a non-default GODEBUG=x509usepolicies=...
   460  		setting.
   461  
   462  	/godebug/non-default-behavior/zipinsecurepath:events
   463  		The number of non-default behaviors executed by the archive/zip
   464  		package due to a non-default GODEBUG=zipinsecurepath=...
   465  		setting.
   466  
   467  	/memory/classes/heap/free:bytes
   468  		Memory that is completely free and eligible to be returned to
   469  		the underlying system, but has not been. This metric is the
   470  		runtime's estimate of free address space that is backed by
   471  		physical memory.
   472  
   473  	/memory/classes/heap/objects:bytes
   474  		Memory occupied by live objects and dead objects that have not
   475  		yet been marked free by the garbage collector.
   476  
   477  	/memory/classes/heap/released:bytes
   478  		Memory that is completely free and has been returned to the
   479  		underlying system. This metric is the runtime's estimate of free
   480  		address space that is still mapped into the process, but is not
   481  		backed by physical memory.
   482  
   483  	/memory/classes/heap/stacks:bytes
   484  		Memory allocated from the heap that is reserved for stack space,
   485  		whether or not it is currently in-use. Currently, this
   486  		represents all stack memory for goroutines. It also includes all
   487  		OS thread stacks in non-cgo programs. Note that stacks may be
   488  		allocated differently in the future, and this may change.
   489  
   490  	/memory/classes/heap/unused:bytes
   491  		Memory that is reserved for heap objects but is not currently
   492  		used to hold heap objects.
   493  
   494  	/memory/classes/metadata/mcache/free:bytes
   495  		Memory that is reserved for runtime mcache structures, but not
   496  		in-use.
   497  
   498  	/memory/classes/metadata/mcache/inuse:bytes
   499  		Memory that is occupied by runtime mcache structures that are
   500  		currently being used.
   501  
   502  	/memory/classes/metadata/mspan/free:bytes
   503  		Memory that is reserved for runtime mspan structures, but not
   504  		in-use.
   505  
   506  	/memory/classes/metadata/mspan/inuse:bytes
   507  		Memory that is occupied by runtime mspan structures that are
   508  		currently being used.
   509  
   510  	/memory/classes/metadata/other:bytes
   511  		Memory that is reserved for or used to hold runtime metadata.
   512  
   513  	/memory/classes/os-stacks:bytes
   514  		Stack memory allocated by the underlying operating system.
   515  		In non-cgo programs this metric is currently zero. This may
   516  		change in the future.In cgo programs this metric includes
   517  		OS thread stacks allocated directly from the OS. Currently,
   518  		this only accounts for one stack in c-shared and c-archive build
   519  		modes, and other sources of stacks from the OS are not measured.
   520  		This too may change in the future.
   521  
   522  	/memory/classes/other:bytes
   523  		Memory used by execution trace buffers, structures for debugging
   524  		the runtime, finalizer and profiler specials, and more.
   525  
   526  	/memory/classes/profiling/buckets:bytes
   527  		Memory that is used by the stack trace hash map used for
   528  		profiling.
   529  
   530  	/memory/classes/total:bytes
   531  		All memory mapped by the Go runtime into the current process
   532  		as read-write. Note that this does not include memory mapped
   533  		by code called via cgo or via the syscall package. Sum of all
   534  		metrics in /memory/classes.
   535  
   536  	/sched/gomaxprocs:threads
   537  		The current runtime.GOMAXPROCS setting, or the number of
   538  		operating system threads that can execute user-level Go code
   539  		simultaneously.
   540  
   541  	/sched/goroutines-created:goroutines
   542  		Count of goroutines created since program start.
   543  
   544  	/sched/goroutines/not-in-go:goroutines
   545  		Approximate count of goroutines running or blocked in
   546  		a system call or cgo call. Not guaranteed to add up to
   547  		/sched/goroutines:goroutines with other goroutine metrics.
   548  
   549  	/sched/goroutines/runnable:goroutines
   550  		Approximate count of goroutines ready to execute,
   551  		but not executing. Not guaranteed to add up to
   552  		/sched/goroutines:goroutines with other goroutine metrics.
   553  
   554  	/sched/goroutines/running:goroutines
   555  		Approximate count of goroutines executing. Always less than or
   556  		equal to /sched/gomaxprocs:threads. Not guaranteed to add up to
   557  		/sched/goroutines:goroutines with other goroutine metrics.
   558  
   559  	/sched/goroutines/waiting:goroutines
   560  		Approximate count of goroutines waiting on a resource
   561  		(I/O or sync primitives). Not guaranteed to add up to
   562  		/sched/goroutines:goroutines with other goroutine metrics.
   563  
   564  	/sched/goroutines:goroutines
   565  		Count of live goroutines.
   566  
   567  	/sched/latencies:seconds
   568  		Distribution of the time goroutines have spent in the scheduler
   569  		in a runnable state before actually running. Bucket counts
   570  		increase monotonically.
   571  
   572  	/sched/pauses/stopping/gc:seconds
   573  		Distribution of individual GC-related stop-the-world stopping
   574  		latencies. This is the time it takes from deciding to stop the
   575  		world until all Ps are stopped. This is a subset of the total
   576  		GC-related stop-the-world time (/sched/pauses/total/gc:seconds).
   577  		During this time, some threads may be executing. Bucket counts
   578  		increase monotonically.
   579  
   580  	/sched/pauses/stopping/other:seconds
   581  		Distribution of individual non-GC-related stop-the-world
   582  		stopping latencies. This is the time it takes from deciding
   583  		to stop the world until all Ps are stopped. This is a
   584  		subset of the total non-GC-related stop-the-world time
   585  		(/sched/pauses/total/other:seconds). During this time, some
   586  		threads may be executing. Bucket counts increase monotonically.
   587  
   588  	/sched/pauses/total/gc:seconds
   589  		Distribution of individual GC-related stop-the-world pause
   590  		latencies. This is the time from deciding to stop the world
   591  		until the world is started again. Some of this time is spent
   592  		getting all threads to stop (this is measured directly in
   593  		/sched/pauses/stopping/gc:seconds), during which some threads
   594  		may still be running. Bucket counts increase monotonically.
   595  
   596  	/sched/pauses/total/other:seconds
   597  		Distribution of individual non-GC-related stop-the-world
   598  		pause latencies. This is the time from deciding to stop the
   599  		world until the world is started again. Some of this time
   600  		is spent getting all threads to stop (measured directly in
   601  		/sched/pauses/stopping/other:seconds). Bucket counts increase
   602  		monotonically.
   603  
   604  	/sched/threads/total:threads
   605  		The current count of live threads that are owned by the Go
   606  		runtime.
   607  
   608  	/sync/mutex/wait/total:seconds
   609  		Approximate cumulative time goroutines have spent blocked on a
   610  		sync.Mutex, sync.RWMutex, or runtime-internal lock. This metric
   611  		is useful for identifying global changes in lock contention.
   612  		Collect a mutex or block profile using the runtime/pprof package
   613  		for more detailed contention data.
   614  */
   615  package metrics
   616  

View as plain text