Benchmarks for various object sizes for FS/XL GetObject (#1984)

benchmark-utils_test.go

@@ -0,0 +1,111 @@
+/*
+ * Minio Cloud Storage, (C) 2016 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"bytes"
+	"crypto/md5"
+	"encoding/hex"
+	"math/rand"
+	"strconv"
+	"testing"
+	"time"
+)
+
+// Creates Object layer setup ( MakeBucket, PutObject) and then runs the benchmark.
+func runGetObjectBenchmark(b *testing.B, obj ObjectLayer, objSize int) {
+	var err error
+	// obtains random bucket name.
+	bucket := getRandomBucketName()
+	// create bucket.
+	err = obj.MakeBucket(bucket)
+	if err != nil {
+		b.Fatal(err)
+	}
+
+	// PutObject returns md5Sum of the object inserted.
+	// md5Sum variable is assigned with that value.
+	var md5Sum string
+	for i := 0; i < 10; i++ {
+		// get text data generated for number of bytes equal to object size.
+		textData := generateBytesData(objSize)
+		// generate md5sum for the generated data.
+		// md5sum of the data to written is required as input for PutObject.
+		// PutObject is the functions which writes the data onto the FS/XL backend.
+		hasher := md5.New()
+		hasher.Write([]byte(textData))
+		metadata := make(map[string]string)
+		metadata["md5Sum"] = hex.EncodeToString(hasher.Sum(nil))
+		// insert the object.
+		md5Sum, err = obj.PutObject(bucket, "object"+strconv.Itoa(i), int64(len(textData)), bytes.NewBuffer(textData), metadata)
+		if err != nil {
+			b.Fatal(err)
+		}
+		if md5Sum != metadata["md5Sum"] {
+			b.Fatalf("Write no: %d: Md5Sum mismatch during object write into the bucket: Expected %s, got %s", i+1, md5Sum, metadata["md5Sum"])
+		}
+	}
+
+	// benchmark utility which helps obtain number of allocations and bytes allocated per ops.
+	b.ReportAllocs()
+	// the actual benchmark for GetObject starts here. Reset the benchmark timer.
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		var buffer = new(bytes.Buffer)
+		err = obj.GetObject(bucket, "object"+strconv.Itoa(i%10), 0, int64(objSize), buffer)
+		if err != nil {
+			b.Error(err)
+		}
+	}
+	// Benchmark ends here. Stop timer.
+	b.StopTimer()
+
+}
+func generateBytesData(size int) []byte {
+	// randomly picks a character and returns its equivalent byte array.
+	getRandomByte := func() []byte {
+		const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+		// seeding the random number generator.
+		rand.Seed(time.Now().UnixNano())
+		var b byte
+		// pick a character randomly.
+		b = letterBytes[rand.Intn(len(letterBytes))]
+		return []byte{b}
+	}
+	// repeat the random character choosen size
+	return bytes.Repeat(getRandomByte(), size)
+}
+
+// creates XL/FS backend setup, obtains the object layer and calls the runGetObjectBenchmark function.
+func benchmarkGetObject(b *testing.B, instanceType string, runBenchMark func(b *testing.B, obj ObjectLayer)) {
+	// create a temp XL/FS backend.
+	objLayer, disks, err := makeTestBackend(instanceType)
+	if err != nil {
+		b.Fatalf("Failed obtaining Temp Backend: <ERROR> %s", err)
+	}
+	// cleaning up the backend by removing all the directories and files created.
+	defer removeRoots(disks)
+	// calling runGetObjectBenchmark which uses *testing.B and the object Layer to run the benchmark.
+	runBenchMark(b, objLayer)
+}
+
+// closure for returning the get object benchmark executor for given object size in bytes.
+func returnGetObjectBenchmark(objSize int) func(*testing.B, ObjectLayer) {
+	return func(b *testing.B, obj ObjectLayer) {
+		runGetObjectBenchmark(b, obj, objSize)
+	}
+}