On Tuesday, 13 December 2016 19:20:04 UTC+11, Stannis Kozlov wrote: > > Thanks for reply, Dave > > I've made simple application and run it on Xeon and i5. In case of i5 I > see threads as expected, on Xeon CPU only one thread is working. May it > related with difference go versions? >
yes, this is why. Before Go 1.5, Go defaulted to one CPU by default. https://golang.org/doc/go1.5 You should upgrade to Go 1.7.4 and prepare to upgrade to Go 1.8 early next year. You are using ancient and unsupported versions of Go. https://github.com/golang/go/wiki/Go-Release-Cycle#release-maintenance > > i5 output (go version 1.6): > $ go run test_tr.go > Spinning thread > Spinning thread > Spinning thread > Spinning thread > Spinning thread > Thread: 4 > Thread: 1 > Thread: 0 > Thread: 2 > > > Xeon output (go version 1.2.1): > $ go run test_tr.go > Spinning thread > Thread: 0 > ^Cexit status 2 > > > > > Code listing: > package main > > > import ( > "fmt" > "math" > "sync" > ) > > > func A1(z int, wg *sync.WaitGroup) { > fmt.Printf("Thread: %v\n",z) > var m, k float64 = 9.99999,9.999999 > var i float64 > for i = 0.0; i < 10000000000; i++ { > math.Sqrt(float64(m*i + k*i)) > } > wg.Done() > } > > > func main() { > var wg sync.WaitGroup > for i := 0; i < 5; i++ { > wg.Add(1) > go A1(i, &wg) > fmt.Println("Spinning thread") > } > wg.Wait() > } > > > On Tuesday, December 13, 2016 at 12:56:50 AM UTC+3, Dave Cheney wrote: >> >> There are no settings to affect the scheduler save GOMAXPROCS. Check that >> none of your code or your dependencies are calling runtime.GOMAXPROCS. >> >> If that doesn't help, try profiling your application, the cpu or block >> profile might tell you where your program is hitting a point of contention. >> >> -- 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. For more options, visit https://groups.google.com/d/optout.
