chg(balancer): Do not wait for request result in Generate().

diff --git a/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go
index 3508bc2..53128e3 100644 (file)
--- a/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go
+++ b/concurrency-is-not-parallelism/balancer_v2/balancer/requester/requester.go
@@ -46,20 +46,26 @@ func furtherProcess(r reqResult) {
 func Generate(work chan<- balancer.Requester) {
     c := make(chan reqResult)
     reqNum := 0
+    t := rand.Intn(5)
+    fmt.Printf("Generate(): sleeping for %v secs\n", t)
+    timeout := time.After(time.Duration(t) * time.Second)
     for {
-        t := rand.Intn(5)
-        fmt.Printf("Generate(): sleeping for %v secs\n", t)
-        time.Sleep(time.Duration(t) * time.Second)
+        select {
+        case <- timeout:
+            req := &request{num: reqNum, c: c}
+            f := func () int { fmt.Printf("... computing %v\n", req); return req.num }
+            req.reqFn = f
+            fmt.Printf("Generate(): sending '%v'\n", req)
+            work <- req
 
-        req := &request{num: reqNum, c: c}
-        f := func () int { fmt.Printf("... computing %v\n", req); return reqNum }
-        req.reqFn = f
-        fmt.Printf("Generate() '%v': sending\n", req)
-        work <- req
-        result := <-c
-        fmt.Printf("Generate() '%v': received result %v\n", req, result)
-        furtherProcess(result)
-        reqNum++
+            t := rand.Intn(5)
+            fmt.Printf("Generate(): sleeping for %v secs\n", t)
+            timeout = time.After(time.Duration(t) * time.Second)
+            reqNum++
+        case result := <-c:
+            fmt.Printf("Generate(): received '%v' result %v\n", result.request, result.int)
+            furtherProcess(result)
+        }
     }
 }