Goroutines

[ardan-bkennedy]

I can't seem to have it report the number of goroutines in my running process? I am using the vars="Goroutines". I do see memory stats

expvarmon -ports="4000" -vars="Goroutines,mem:memstats.HeapInuse"

[divan]

Hi,

Does "Goroutines" field is present in /debug/vars JSON?

Whit is the output of the following command?
curl -s http://localhost:4000/debug/vars | grep Goroutines

[maded2]

Using Go 1.5.4 - Goroutines is not exported in the /debug/vars JSON

here's json for memstat:

"memstats": {"Alloc":5499512,"TotalAlloc":504807448,"Sys":18983224,"Lookups":420,"Mallocs":8856735,"Frees":8798054,"HeapAlloc":5499512,"HeapSys":9928704,"HeapIdle":2220032,"HeapInuse":7708672,"HeapReleased":0,"HeapObjects":58681,"StackInuse":1605632,"StackSys":1605632,"MSpanInuse":95424,"MSpanSys":114688,"MCacheInuse":9664,"MCacheSys":16384,"BuckHashSys":1514836,"GCSys":375808,"OtherSys":5427172,"NextGC":7305090,"LastGC":1460213329874430150,"PauseTotalNs":41081667,"PauseNs":[424640,360910,183002,308915,185596,272903,340900,308836,285361,248796,362968,254382,182209,317215,503425,254707,255963,244918,357311,259579,268391,435154,262704,235397,248977,228154,300874,203720,253363,233115,212842,349334,276849,226944,244197,183586,263154,236516,327651,255430,185573,216214,197735,213513,358075,252029,279676,275459,256201,257779,263048,197512,290664,259778,253963,251716,519012,262333,329473,259796,234458,252393,211881,280516,210608,272262,257206,249624,256743,268125,239731,277310,265276,297404,258137,184806,188294,195857,288548,373749,430788,264243,199819,201113,196004,208040,297842,189894,197500,333817,283296,255623,321814,231649,295664,313473,231542,316965,366752,318756,255302,256307,258630,259000,264199,331680,263610,209958,268625,244055,327139,258554,282879,286830,328837,326887,558210,215492,297057,220980,262948,306264,355643,286714,325603,228056,376459,203576,575990,320769,252729,204286,270356,275685,215305,338613,411549,259255,221400,236319,335821,227790,198892,337678,321432,398179,353953,210213,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],"PauseEnd":[1460212419950871012,1460212419964380563,1460212420220828563,1460212420228441950,1460212421195328267,1460212425887929770,1460212436317007080,1460212440698388367,1460212444372459685,1460212451700262166,1460212460698138060,1460212465556566933,1460212474262065841,1460212479806197906,1460212480750406760,1460212484719613564,1460212491451765323,1460212498859512834,1460212501032495329,1460212507505496596,1460212516561580170,1460212520706652823,1460212526998940122,1460212533638297809,1460212539488789265,1460212540702478322,1460212543942313749,1460212550390991767,1460212555305970794,1460212560100522604,1460212561948004665,1460212567536676955,1460212573649531225,1460212579845034405,1460212581723236203,1460212587221023191,1460212592875304274,1460212598911932278,1460212600722742043,1460212603099921119,1460212608241035156,1460212613340041163,1460212618367189794,1460212620713124886,1460212626555847635,1460212633978161092,1460212640016505856,1460212642551013442,1460212648060348511,1460212655564274446,1460212660254460493,1460212661236503560,1460212665191745302,1460212670926605167,1460212675599805215,1460212680449961491,1460212683339336899,1460212688971212377,1460212695132309267,1460212700384061148,1460212703246259344,1460212708975488953,1460212714612301782,1460212719783090499,1460212720882960408,1460212724257283836,1460212729833241739,1460212735020197142,1460212739961165527,1460212742796185881,1460212747850461143,1460212755314818636,1460212760947416073,1460212764715222523,1460212770562845973,1460212777509808380,1460212780732122663,1460212782491587660,1460212790988688864,1460212799279629287,1460212802180938522,1460212809175243055,1460212817745878549,1460212821181578317,1460212828567023009,1460212836511786719,1460212840625146596,1460212842339605136,1460212848859731749,1460212852634971087,1460212859516327363,1460212861882887719,1460212865396459920,1460212875724584455,1460212880993620814,1460212892053011352,1460212899799978150,1460212901548388177,1460212910988913695,1460212919833307051,1460212922619606550,1460212934426757594,1460212940632855274,1460212949486876000,1460212960081794732,1460212961672009262,1460212971005375427,1460212980600987938,1460212991671877178,1460213000605815386,1460213017012923605,1460213020825394431,1460213028419920207,1460213040042018782,1460213045661490982,1460213059496912728,1460213064128832155,1460213076108555505,1460213080634739154,1460213084638866806,1460213100085900271,1460213107534675249,1460213119816205453,1460213125013746401,1460213139782691091,1460213141123717813,1460213151056503519,1460213160103944807,1460213163459158051,1460213177568909007,1460213184350937079,1460213193225009242,1460213200762737302,1460213206479336667,1460213213695758997,1460213220659560776,1460213228222632480,1460213239980965312,1460213247123212412,1460213259801080752,1460213261157386234,1460213271021219625,1460213280606571893,1460213292471086938,1460213300616709759,1460213314414704408,1460213320632255120,1460213329874430150,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0],"NumGC":148,"GCCPUFraction":7.02748399173599e-05,"EnableGC":true,"DebugGC":false,"BySize":[{"Size":0,"Mallocs":0,"Frees":0},{"Size":8,"Mallocs":9419,"Frees":9270},{"Size":16,"Mallocs":6131414,"Frees":6100067},{"Size":32,"Mallocs":1157872,"Frees":1144694},{"Size":48,"Mallocs":751985,"Frees":747895},{"Size":64,"Mallocs":222323,"Frees":219503},{"Size":80,"Mallocs":22543,"Frees":22038},{"Size":96,"Mallocs":46979,"Frees":46302},{"Size":112,"Mallocs":58241,"Frees":57577},{"Size":128,"Mallocs":34371,"Frees":34130},{"Size":144,"Mallocs":15784,"Frees":15701},{"Size":160,"Mallocs":35943,"Frees":35310},{"Size":176,"Mallocs":28585,"Frees":28328},{"Size":192,"Mallocs":9938,"Frees":9836},{"Size":208,"Mallocs":2185,"Frees":2111},{"Size":224,"Mallocs":32695,"Frees":32276},{"Size":240,"Mallocs":80109,"Frees":79288},{"Size":256,"Mallocs":10838,"Frees":10682},{"Size":288,"Mallocs":32367,"Frees":32105},{"Size":320,"Mallocs":6447,"Frees":6090},{"Size":352,"Mallocs":2229,"Frees":2198},{"Size":384,"Mallocs":446,"Frees":157},{"Size":416,"Mallocs":497,"Frees":459},{"Size":448,"Mallocs":1148,"Frees":1070},{"Size":480,"Mallocs":497,"Frees":489},{"Size":512,"Mallocs":74329,"Frees":74067},{"Size":576,"Mallocs":2917,"Frees":2829},{"Size":640,"Mallocs":145,"Frees":137},{"Size":704,"Mallocs":1905,"Frees":1867},{"Size":768,"Mallocs":525,"Frees":521},{"Size":896,"Mallocs":968,"Frees":899},{"Size":1024,"Mallocs":786,"Frees":711},{"Size":1152,"Mallocs":818,"Frees":504},{"Size":1280,"Mallocs":77,"Frees":64},{"Size":1408,"Mallocs":2482,"Frees":2449},{"Size":1536,"Mallocs":68292,"Frees":68046},{"Size":1664,"Mallocs":58,"Frees":46},{"Size":2048,"Mallocs":417,"Frees":396},{"Size":2304,"Mallocs":214,"Frees":206},{"Size":2560,"Mallocs":1084,"Frees":1082},{"Size":2816,"Mallocs":77,"Frees":75},{"Size":3072,"Mallocs":18,"Frees":15},{"Size":3328,"Mallocs":303,"Frees":297},{"Size":4096,"Mallocs":2147,"Frees":2090},{"Size":4608,"Mallocs":1393,"Frees":1378},{"Size":5376,"Mallocs":180,"Frees":165},{"Size":6144,"Mallocs":275,"Frees":268},{"Size":6400,"Mallocs":33,"Frees":33},{"Size":6656,"Mallocs":30,"Frees":28},{"Size":6912,"Mallocs":16,"Frees":16},{"Size":8192,"Mallocs":612,"Frees":566},{"Size":8448,"Mallocs":302,"Frees":302},{"Size":8704,"Mallocs":32,"Frees":31},{"Size":9472,"Mallocs":115,"Frees":113},{"Size":10496,"Mallocs":0,"Frees":0},{"Size":12288,"Mallocs":4,"Frees":2},{"Size":13568,"Mallocs":0,"Frees":0},{"Size":14080,"Mallocs":0,"Frees":0},{"Size":16384,"Mallocs":81,"Frees":78},{"Size":16640,"Mallocs":40,"Frees":0},{"Size":17664,"Mallocs":5,"Frees":3}]},

[divan]

Oh right, expvar package doesn't export goroutines number. It should be done via expvar.Func, something like this:

func goroutines() interface{} {
    return runtime.NumGoroutine()
}
...
expvar.Publish("Goroutines", expvar.Func(goroutines))

I guess README misleads people to think that Goroutines is exported, but it's not. Any suggestions how to improve?

[maded2]

gr:= expvar.NewInt("Goroutines")
go func() {
for _ = range time.Tick(d) {
gr.Set(int64(runtime.NumGoroutine()))
}

[dgryski]

@maded2 The solution from @divan only calls NumGoroutine() when requested and doesn't spawn an extra goroutine just to set this one constant.

[ardan-bkennedy]

Goroutines are working now. I didn't realize you can add your own metrics. This is cool.

[ardan-bkennedy]

is there a published list of default variables?

[divan]

is there a published list of default variables?

Sorry for delay (half a year one) with response :) The list is available as part of the expvarmon --help output.