[checks] introduce semaphore

mackerelio · Jan 15, 2019 · 00a1ef0 · 00a1ef0
1 parent 2eacd45
commit 00a1ef0
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/checks/checker.go b/checks/checker.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"runtime"
 	"strings"
 	"sync"
 
@@ -111,13 +112,16 @@ type checker interface {
 func runChecks(checkers []checker, w io.Writer) error {
 	ch := make(chan *result)
 	total := len(checkers)
+	sem := make(chan struct{}, runtime.NumCPU()*2)
 	go func() {
 		wg := &sync.WaitGroup{}
 		wg.Add(total)
 		for _, c := range checkers {
 			go func(c checker) {
 				defer wg.Done()
+				sem <- struct{}{}
 				ch <- c.check()
+				<-sem
 			}(c)
 		}
 		wg.Wait()