{ "program_id": "02_multiple_goroutines", "program_source": "// WEAVE_META\n// outcome: success\n// concurrency_pattern: fanout\n// goroutine_count: 4\n// expected_nondeterminism: medium\n// description: main fans out work to three goroutines and collects results through a shared results channel.\n\npackage main\n\nimport (\n\t\"fmt\"\n\t\"os\"\n\t\"runtime/trace\"\n\t\"sync\"\n)\n\nfunc main() {\n\tif tf := os.Getenv(\"WEAVE_TRACE_FILE\"); tf != \"\" {\n\t\tf, err := os.Create(tf)\n\t\tif err == nil {\n\t\t\tif err := trace.Start(f); err == nil {\n\t\t\t\tdefer func() { trace.Stop(); f.Close() }()\n\t\t\t}\n\t\t}\n\t}\n\n\tjobs := []int{10, 20, 30}\n\tresults := make(chan int, len(jobs))\n\tvar wg sync.WaitGroup\n\n\tfor _, j := range jobs {\n\t\twg.Add(1)\n\t\tgo func(n int) {\n\t\t\tdefer wg.Done()\n\t\t\tresults \u003c- n * n\n\t\t}(j)\n\t}\n\n\tgo func() {\n\t\twg.Wait()\n\t\tclose(results)\n\t}()\n\n\tfor r := range results {\n\t\tfmt.Println(r)\n\t}\n}\n", "partial_trace": [ { "event_id": 0, "timestamp_ns": 14703706862208, "event_type": "GoCreate", "goroutine_id": 7, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" } }, "channels": {}, "mutexes": {} }, { "event_id": 1, "timestamp_ns": 14703706868032, "event_type": "GoCreate", "goroutine_id": 8, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" } }, "channels": {}, "mutexes": {} }, { "event_id": 2, "timestamp_ns": 14703706878656, "event_type": "GoCreate", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 3, "timestamp_ns": 14703706885696, "event_type": "GoCreate", "goroutine_id": 10, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 4, "timestamp_ns": 14703706889920, "event_type": "GoCreate", "goroutine_id": 11, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 5, "timestamp_ns": 14703706890816, "event_type": "GoCreate", "goroutine_id": 12, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 6, "timestamp_ns": 14703706891904, "event_type": "GoCreate", "goroutine_id": 13, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 7, "timestamp_ns": 14703706893952, "event_type": "GoBlock", "goroutine_id": 1, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.traceStartReadCPU" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 8, "timestamp_ns": 14703706894464, "event_type": "GoStart", "goroutine_id": 7, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 9, "timestamp_ns": 14703706894528, "event_type": "GoStart", "goroutine_id": 13, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 10, "timestamp_ns": 14703706903616, "event_type": "GoBlock", "goroutine_id": 13, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.(*traceAdvancerState).start" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 11, "timestamp_ns": 14703706904192, "event_type": "GoStart", "goroutine_id": 8, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "9": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked" } }, "channels": {}, "mutexes": {} }, { "event_id": 12, "timestamp_ns": 14703706916032, "event_type": "GoStart", "goroutine_id": 9, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 13, "timestamp_ns": 14703706925248, "event_type": "GoBlock", "goroutine_id": 8, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 14, "timestamp_ns": 14703706925504, "event_type": "GoStart", "goroutine_id": 11, "goroutines": { "1": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv2" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 15, "timestamp_ns": 14703706931456, "event_type": "GoUnblock", "goroutine_id": 1, "goroutines": { "1": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.chansend1" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "11": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 16, "timestamp_ns": 14703706933248, "event_type": "GoEnd", "goroutine_id": 11, "goroutines": { "1": { "status": "runnable", "blocked_on": null, "locals_hint": "runtime.chansend1" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 17, "timestamp_ns": 14703706933632, "event_type": "GoStart", "goroutine_id": 1, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 18, "timestamp_ns": 14703706941696, "event_type": "GoBlock", "goroutine_id": 7, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 19, "timestamp_ns": 14703706942208, "event_type": "GoStart", "goroutine_id": 10, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "10": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 20, "timestamp_ns": 14703706950784, "event_type": "GoEnd", "goroutine_id": 10, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 21, "timestamp_ns": 14703706955968, "event_type": "GoBlock", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": "syscall", "locals_hint": "syscall.syscall" } }, "channels": {}, "mutexes": {} }, { "event_id": 22, "timestamp_ns": 14703706988864, "event_type": "GoStart", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "runnable", "blocked_on": null, "locals_hint": "main.main" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 23, "timestamp_ns": 14703706989440, "event_type": "GoStart", "goroutine_id": 12, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 24, "timestamp_ns": 14703706991360, "event_type": "GoBlock", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": "syscall", "locals_hint": "syscall.syscall" } }, "channels": {}, "mutexes": {} }, { "event_id": 25, "timestamp_ns": 14703706995840, "event_type": "GoStart", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "running", "blocked_on": null, "locals_hint": "unknown" } }, "channels": {}, "mutexes": {} }, { "event_id": 26, "timestamp_ns": 14703706996416, "event_type": "GoBlock", "goroutine_id": 9, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "13": { "status": "blocked", "blocked_on": "sync", "locals_hint": "sync.(*WaitGroup).Wait" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "blocked", "blocked_on": "system goroutine wait", "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1" } }, "channels": {}, "mutexes": {} } ], "next_event": { "event_id": 27, "timestamp_ns": 14703706998720, "event_type": "GoUnblock", "goroutine_id": 13, "goroutines": { "1": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "12": { "status": "running", "blocked_on": null, "locals_hint": "unknown" }, "13": { "status": "runnable", "blocked_on": null, "locals_hint": "sync.(*WaitGroup).Add" }, "7": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "8": { "status": "blocked", "blocked_on": "chan receive", "locals_hint": "runtime.chanrecv1" }, "9": { "status": "blocked", "blocked_on": "system goroutine wait", "locals_hint": "runtime/trace.(*traceMultiplexer).startLocked.func1" } }, "channels": {}, "mutexes": {} }, "full_outcome": "success", "concurrency_pattern": "fanout", "goroutine_count": 4, "nondeterminism": "medium", "run_index": 2, "split_percent": 75, "timed_out": false }