fix: align properly fields which are updated atomically

This fixes alignment of the fields on 32-bit arches.

Fixes #30

Signed-off-by: Andrey Smirnov <[email protected]>

.github/workflows/lint.yml

@@ -0,0 +1,12 @@
+on: [push, pull_request]
+name: Lint
+jobs:
+  golangci:
+      name: lint
+      runs-on: ubuntu-latest
+      steps:
+        - uses: actions/checkout@v2
+        - name: golangci-lint
+          uses: golangci/golangci-lint-action@v2
+          with:
+            version: v1.28

.github/workflows/test.yml

@@ -0,0 +1,22 @@
+on: [push, pull_request]
+name: Test
+jobs:
+  test:
+    strategy:
+      matrix:
+        go-version: [1.14.x, 1.15.x]
+        os: [ubuntu-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+    - name: Install Go
+      uses: actions/setup-go@v2
+      with:
+        go-version: ${{ matrix.go-version }}
+    - name: Checkout code
+      uses: actions/checkout@v2
+    - name: Test
+      run: go test -v ./...
+    - name: Test Race
+      run: go test -v -race ./...
+    - name: Bench
+      run: go test -v -bench . -benchmem -run nothing ./...

client.go

@@ -41,6 +41,11 @@ type Client struct {
 }
 
 type transport struct {
+	// these fields are updated with atomic operations,
+	// so they should be at the top for proper alignment
+	lostPacketsPeriod  int64
+	lostPacketsOverall int64
+
 	maxPacketSize int
 	tagFormat     *TagFormat
 
@@ -53,9 +58,6 @@ type transport struct {
 	shutdown     chan struct{}
 	shutdownOnce sync.Once
 	shutdownWg   sync.WaitGroup
-
-	lostPacketsPeriod  int64
-	lostPacketsOverall int64
 }
 
 // NewClient creates new statsd client and starts background processing

client_test.go

@@ -43,7 +43,7 @@ func setupListener(t *testing.T) (*net.UDPConn, chan []byte) {
 		t.Error(err)
 	}
 
-	received := make(chan []byte)
+	received := make(chan []byte, 1024)
 
 	go func() {
 		for {
@@ -305,8 +305,8 @@ func TestConcurrent(t *testing.T) {
 		wg1.Done()
 	}()
 
-	workers := 32
-	count := 4096
+	workers := 16
+	count := 1024
 
 	for i := 0; i < workers; i++ {
 		wg2.Add(1)
@@ -334,7 +334,14 @@ func TestConcurrent(t *testing.T) {
 
 	_ = client.Close()
 
-	time.Sleep(time.Second)
+	// wait for 10 seconds for all the packets to be received
+	for i := 0; i < 10; i++ {
+		if atomic.LoadInt64(&totalSent) == atomic.LoadInt64(&totalReceived) {
+			break
+		}
+
+		time.Sleep(time.Second)
+	}
 
 	_ = inSocket.Close()
 	close(received)