### Threads

#### Application's calling thread

The application-layer must block on writing I/O. We can't return from a write until we've pushed its bytes onto the socket. Otherwise, if the write fails we are unable to deliver its IOException to the application. We would have told the application layer that the write succeeded, but it didn't!

	obj, err := newObjectLayer(ctx, mustGetPoolEndpoints(0, disks...))
	if err != nil {
		t.Fatal("Unexpected object layer initialization error", err)
	}

	_, ok := obj.(*erasureServerPools)
	if !ok {
		t.Fatal("Unexpected object layer detected", reflect.TypeOf(obj))
	}

	// Tests for Erasure object layer initialization.

	// Create temporary backend for the test server.
	nDisks = 16
	disks, err = getRandomDisks(nDisks)

	defer removeRoots(disks)

	// uses *testing.B and the object Layer to run the benchmark.
	runPutObjectPartBenchmark(b, objLayer, objSize)
}

// creates Erasure/FS backend setup, obtains the object layer and calls the runPutObjectBenchmark function.
func benchmarkPutObject(b *testing.B, instanceType string, objSize int) {
	// create a temp Erasure/FS backend.

	deletedBucketsPrefix = ".deleted"

	// ETag (hex encoded md5sum) of empty string.
	emptyETag = "d41d8cd98f00b204e9800998ecf8427e"
)

// Global object layer mutex, used for safely updating object layer.
var globalObjLayerMutex sync.RWMutex

// Global object layer, only accessed by globalObjectAPI.
var globalObjectAPI ObjectLayer

type storageOpts struct {
	cleanUp     bool
	healthCheck bool
}

	tmpPath := t.TempDir()
	testCases := []struct {
		volName       string
		expectedUmask int
	}{
		{"is-this-valid", getUmask()},
	}
	testCase := testCases[0]

	// Initialize a new xlStorage layer.
	disk, err := newLocalXLStorage(tmpPath)
	if err != nil {
		t.Fatalf("Initializing xlStorage failed with %s.", err)
	}

	// Attempt to create a volume to verify the permissions later.
	// MakeVol creates 0777.

	nilReq, err := newTestRequest(http.MethodGet, getBucketLocationURL("", nilBucket), 0, nil)
	if err != nil {
		t.Errorf("MinIO %s: Failed to create HTTP request for testing the response when object Layer is set to `nil`.", instanceType)
	}
	// Executes the object layer set to `nil` test.
	// `ExecObjectLayerAPINilTest` manages the operation.
	ExecObjectLayerAPINilTest(t, nilBucket, "", instanceType, apiRouter, nilReq)
}

	}
}

// ExecObjectLayerAPINilTest - Sets the object layer to `nil`, and calls the registered object layer API endpoint,
// and assert the error response. The purpose is to validate the API handlers response when the object layer is uninitialized.

   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *

~~ under the License.

 -----
 Introduction
 -----
 Hervé Boutemy
 -----
 2016-05-29
 -----

Maven Compat

 Maven2 classes maintained as compatibility layer for plugins that need to keep Maven2 compatibility.

 Plugins should avoid these classes and be updated to use only Maven3 dependencies (and require Maven3): see

   * sent.
   */
  private fun recover(
    e: IOException,
    call: RealCall,
    userRequest: Request,
    requestSendStarted: Boolean,
  ): Boolean {
    // The application layer has forbidden retries.
    if (!client.retryOnConnectionFailure) return false

    // We can't send the request body again.
    if (requestSendStarted && requestIsOneShot(e, userRequest)) return false