Hi Robert, Sorry I missed your earlier response.
>From what we saw our UI was blocked and since everything was unresponsive we had to recover the system by sending sig abort. On Mon, Aug 24, 2020 at 4:11 PM Siddhesh Divekar <siddhesh.dive...@gmail.com> wrote: > Looking at the no. of go routines we have does this apply to this issue ? > https://github.com/golang/go/issues/27044 > > On Mon, Aug 24, 2020 at 12:54 PM Robert Engels <reng...@ix.netcom.com> > wrote: > >> Go routines in a waiting state should not be consuming CPU. Are you >> certain they are not in constant transition from waiting to processing - >> this could show up as high CPU usage while everything looks blocks. >> >> I would use pprof - github.com/robaho/goanalyzer might be of assistance >> here to see the actual work being done. >> >> On Aug 24, 2020, at 9:10 AM, Siddhesh Divekar <siddhesh.dive...@gmail.com> >> wrote: >> >> >> Hi Ian, >> >> Thanks for replying. >> >> We have a go server running which handles user requests & collects data >> from various sources like gcp's cloud sql and big query. >> We are using shopify's sarama library to do kafka operations. >> >> There are seeing lots of go routines in waiting state for several >> minutes. >> Over the period of time around 587 goroutines have been spun up. >> >> We see that two go routines are stuck on gcp big query and we are using >> wait groups there. >> However, it's not clear why that would cause all other go routines to get >> hung & make cpu go high. >> >> goroutine 3332131 [semacquire, 79 minutes]: >> sync.runtime_Semacquire(0xc001c4fcf8) >> /usr/local/go/src/runtime/sema.go:56 +0x42 >> sync.(*WaitGroup).Wait(0xc001c4fcf0) >> /usr/local/go/src/sync/waitgroup.go:130 +0x64 >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*InsMgr).runParallelQuery(0xc001b54d40, >> 0xc002912c00, 0x330e1b0, 0xf, 0xc002912cf0, 0x3) >> /builds/fusionio/fusion/controller/stats/ins_mgr.go:488 +0x1d7 >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*InsMgr).GetMainUi(0xc001b54d40, >> 0xc002912db8, 0xc001870e68, 0x746121, 0xc0010fcaf8, 0x17) >> /builds/fusionio/fusion/controller/stats/ins_mgr.go:567 +0xa0d >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*Prefetcher).fetchMainUiTeamInterval(0xc001b56780, >> 0xc002356810, 0x24, 0x32f7b78, 0x5) >> /builds/fusionio/fusion/controller/stats/prefetcher.go:77 +0xf2 >> created by >> git.fusion.io/fusionio/fusion/controller.git/stats.(*Prefetcher).prefetchStats >> /builds/fusionio/fusion/controller/stats/prefetcher.go:100 +0xd8 >> >> >> goroutine 3332149 [semacquire, 79 minutes]: >> sync.runtime_Semacquire(0xc0015ede48) >> /usr/local/go/src/runtime/sema.go:56 +0x42 >> sync.(*WaitGroup).Wait(0xc0015ede40) >> /usr/local/go/src/sync/waitgroup.go:130 +0x64 >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*InsMgr).runParallelQuery(0xc001b54d40, >> 0xc00249dc00, 0x330e1b0, 0xf, 0xc00249dcf0, 0x3) >> /builds/fusionio/fusion/controller/stats/ins_mgr.go:488 +0x1d7 >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*InsMgr).GetMainUi(0xc001b54d40, >> 0xc00249ddb8, 0xc003200668, 0xc00407a520, 0xc003200590, 0x46ee97) >> /builds/fusionio/fusion/controller/stats/ins_mgr.go:567 +0xa0d >> >> git.fusion.io/fusionio/fusion/controller.git/stats.(*Prefetcher).fetchMainUiTeamInterval(0xc001b56780, >> 0xc002356ba0, 0x24, 0x32f7b78, 0x5) >> /builds/fusionio/fusion/controller/stats/prefetcher.go:77 +0xf2 >> created by >> git.fusion.io/fusionio/fusion/controller.git/stats.(*Prefetcher).prefetchStats >> /builds/fusionio/fusion/controller/stats/prefetcher.go:100 +0xd8 >> >> I found the link below which kind of co-relates to our scenario. >> >> https://stackoverflow.com/questions/42238695/goroutine-in-io-wait-state-for-long-time >> >> Most of the go routines in the backtrace are in a net/http package so our >> suspicion is that above bug in our code might be causing that. >> Even the bigquery is getting hung in net/http. >> >> We are using go version 1.13.8 & are running on gcp kubernetes cluster on >> ubuntu 18.04 docker. >> >> go env >> GO111MODULE="" >> GOARCH="amd64" >> GOBIN="" >> GOCACHE="/root/.cache/go-build" >> GOENV="/root/.config/go/env" >> GOEXE="" >> GOFLAGS="" >> GOHOSTARCH="amd64" >> GOHOSTOS="linux" >> GONOPROXY="" >> GONOSUMDB="" >> GOOS="linux" >> GOPATH="/root/go" >> GOPRIVATE="" >> GOPROXY="https://proxy.golang.org,direct"; >> GOROOT="/usr/local/go" >> GOSUMDB="sum.golang.org" >> GOTMPDIR="" >> GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64" >> GCCGO="gccgo" >> AR="ar" >> CC="gcc" >> CXX="g++" >> CGO_ENABLED="1" >> GOMOD="/builds/prosimoio/prosimo/pdash/go.mod" >> CGO_CFLAGS="-g -O2" >> CGO_CPPFLAGS="" >> CGO_CXXFLAGS="-g -O2" >> CGO_FFLAGS="-g -O2" >> CGO_LDFLAGS="-g -O2" >> PKG_CONFIG="pkg-config" >> GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 >> -fdebug-prefix-map=/tmp/go-build048009048=/tmp/go-build >> -gno-record-gcc-switches" >> >> Let me know if any other information is needed. >> >> >> On Sat, Aug 22, 2020 at 12:30 PM Ian Lance Taylor <i...@golang.org> >> wrote: >> >>> On Sat, Aug 22, 2020 at 12:06 PM Siddhesh Divekar >>> <siddhesh.dive...@gmail.com> wrote: >>> > >>> > We saw an issue with our process running in k8s on ubuntu 18.04. >>> > Most of the go routines are stuck for several minutes in http/http2 >>> net code. >>> > >>> > Have you seen similar issues ? >>> > >>> > goroutine 2800143 [select, 324 minutes]: >>> net/http.(*persistConn).readLoop(0xc00187d440) >>> /usr/local/go/src/net/http/transport.go:2032 +0x999 created by >>> net/http.(*Transport).dialConn /usr/local/go/src/net/http/transport.go:1580 >>> +0xb0d goroutine 2738894 [IO wait, 352 minutes]: >>> internal/poll.runtime_pollWait(0x7f5b61b280c0, 0x72, 0xffffffffffffffff) >>> /usr/local/go/src/runtime/netpoll.go:184 +0x55 >>> internal/poll.(*pollDesc).wait(0xc0017e7e18, 0x72, 0x1000, 0x1000, >>> 0xffffffffffffffff) /usr/local/go/src/internal/poll/fd_poll_runtime.go:87 >>> +0x45 internal/poll.(*pollDesc).waitRead(...) >>> /usr/local/go/src/internal/poll/fd_poll_runtime.go:92 >>> internal/poll.(*FD).Read(0xc0017e7e00, 0xc0044a9000, 0x1000, 0x1000, 0x0, >>> 0x0, 0x0) /usr/local/go/src/internal/poll/fd_unix.go:169 +0x1cf >>> net.(*netFD).Read(0xc0017e7e00, 0xc0044a9000, 0x1000, 0x1000, 0xc0026359e8, >>> 0x49d7fd, 0xc0017e7e00) /usr/local/go/src/net/fd_unix.go:202 +0x4f >>> net.(*conn).Read(0xc0000db8b8, 0xc0044a9000, 0x1000, 0x1000, 0x0, 0x0, 0x0) >>> /usr/local/go/src/net/net.go:184 +0x68 >>> net/http.(*connReader).Read(0xc004a4fec0, 0xc0044a9000, 0x1000, 0x1000, >>> 0x0, 0x0, 0x0) /usr/local/go/src/net/http/server.go:785 +0xf4 >>> bufio.(*Reader).fill(0xc003f1a360) /usr/local/go/src/bufio/bufio.go:100 >>> +0x103 bufio.(*Reader).Peek(0xc003f1a360, 0x4, 0x0, 0x0, 0x0, 0x0, >>> 0xc002635ad0) /usr/local/go/src/bufio/bufio.go:138 +0x4f >>> net/http.(*conn).readRequest(0xc0028e1d60, 0x393ed20, 0xc0024e9780, 0x0, >>> 0x0, 0x0) /usr/local/go/src/net/http/server.go:962 +0xb3b >>> net/http.(*conn).serve(0xc0028e1d60, 0x393ed20, 0xc0024e9780) >>> /usr/local/go/src/net/http/server.go:1817 +0x6d4 created by >>> net/http.(*Server).Serve /usr/local/go/src/net/http/server.go:2928 +0x384 >>> > >>> > Is there a know issue or something obvious from the backtrace here. >>> >>> It's entirely normal for goroutines to sit in pollWait if they are >>> waiting for network I/O. There may be reasons why this is incorrect >>> for your program, but you'll have to tell us those reasons. >>> >>> Also, along with those reasons, please tell us the version of Go and >>> the exact environment that you are running. Thanks. >>> >>> Ian >>> >> >> >> -- >> -Siddhesh. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/CAMjfk%2BggC%2BwgwM_%2BM5ML0SKD3qJphCrif%3D4c2AqB9v6n%2Btw5Jw%40mail.gmail.com >> <https://groups.google.com/d/msgid/golang-nuts/CAMjfk%2BggC%2BwgwM_%2BM5ML0SKD3qJphCrif%3D4c2AqB9v6n%2Btw5Jw%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> <backtrace.txt> >> >> > > -- > -Siddhesh. > -- -Siddhesh. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CAMjfk%2BiRY8UAgS4YjaYBwXEY80xU2cqy-3zhPcdgRVQHxvdXbA%40mail.gmail.com.
