Introduction
Notes on the runtime package in concurrent Go programming
Yielding CPU Time Slice
- Whenever a goroutine executes
runtime.Gosched(), it immediately yields its current time slice to allow other goroutines to execute.
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| package main
import "runtime"
func task() {
...
}
func main() {
go task()
for i := 0; i < 3; i++ {
runtime.Gosched()
}
}
|
Exiting Current Goroutine
- Whenever a goroutine executes
runtime.Goexit(), it immediately exits the current goroutine.
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| package main
import "runtime"
func task() {
for i := 0; i < 3; i++ {
...
if i == 2 {
runtime.Goexit()
}
}
}
func main() {
go task()
}
|
Checking Number of CPU Cores in the Host
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| import "runtime"
func main() {
runtime.NumCPU()
}
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Specifying the Number of CPU Cores to Use
go1.5 and earlier versions default to using 1 core, while go1.5 and later versions default to using the maximum number of cores in the host.
<num>: The maximum number of cores the Go program is allowed to use.
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| import "runtime"
func main() {
runtime.GOMAXPROCS(<num>)
}
|
Conclusion
References
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