Исходники и презентации

lessons/sync_primitives/starvation/main.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"fmt"
+	"sync"
+	"time"
+)
+
+// Starvation may be with processor, memory, file descriptors,
+// connections with database and so on...
+
+func main() {
+	var wg sync.WaitGroup
+	var mutex sync.Mutex
+	const runtime = 1 * time.Second
+
+	greedyWorker := func() {
+		defer wg.Done()
+
+		var count int
+		for begin := time.Now(); time.Since(begin) <= runtime; {
+			mutex.Lock()
+			time.Sleep(3 * time.Nanosecond)
+			mutex.Unlock()
+			count++
+		}
+
+		fmt.Printf("Greedy worker was able to execute %v work loops\n", count)
+	}
+
+	politeWorker := func() {
+		defer wg.Done()
+
+		var count int
+		for begin := time.Now(); time.Since(begin) <= runtime; {
+			mutex.Lock()
+			time.Sleep(1 * time.Nanosecond)
+			mutex.Unlock()
+
+			mutex.Lock()
+			time.Sleep(1 * time.Nanosecond)
+			mutex.Unlock()
+
+			mutex.Lock()
+			time.Sleep(1 * time.Nanosecond)
+			mutex.Unlock()
+
+			count++
+		}
+
+		fmt.Printf("Polite worker was able to execute %v work loops.\n", count)
+	}
+
+	wg.Add(2)
+	go greedyWorker()
+	go politeWorker()
+
+	wg.Wait()
+}