diff --git a/eth/tracers/api_test.go b/eth/tracers/api_test.go
index 0032e6794d..2187b4abd1 100644
--- a/eth/tracers/api_test.go
+++ b/eth/tracers/api_test.go
@@ -64,6 +64,8 @@ type testBackend struct {
 	relHook func() // Hook is invoked when the requested state is released
 }
 
+// testBackend creates a new test backend. OBS: After test is done, teardown must be
+// invoked in order to release associated resources.
 func newTestBackend(t *testing.T, n int, gspec *core.Genesis, generator func(i int, b *core.BlockGen)) *testBackend {
 	backend := &testBackend{
 		chainConfig: gspec.Config,
@@ -141,6 +143,11 @@ func (b *testBackend) ChainDb() ethdb.Database {
 	return b.chaindb
 }
 
+// teardown releases the associated resources.
+func (b *testBackend) teardown() {
+	b.chain.Stop()
+}
+
 func (b *testBackend) StateAtBlock(ctx context.Context, block *types.Block, reexec uint64, base *state.StateDB, readOnly bool, preferDisk bool) (*state.StateDB, StateReleaseFunc, error) {
 	statedb, err := b.chain.StateAt(block.Root())
 	if err != nil {
@@ -204,13 +211,15 @@ func TestTraceCall(t *testing.T) {
 		}}
 	genBlocks := 10
 	signer := types.HomesteadSigner{}
-	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
+	backend := newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
 		// Transfer from account[0] to account[1]
 		//    value: 1000 wei
 		//    fee:   0 wei
 		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
 		b.AddTx(tx)
-	}))
+	})
+	defer backend.teardown()
+	api := NewAPI(backend)
 	var testSuite = []struct {
 		blockNumber rpc.BlockNumber
 		call        ethapi.TransactionArgs
@@ -337,14 +346,16 @@ func TestTraceTransaction(t *testing.T) {
 		}}
 	target := common.Hash{}
 	signer := types.HomesteadSigner{}
-	api := NewAPI(newTestBackend(t, 1, genesis, func(i int, b *core.BlockGen) {
+	backend := newTestBackend(t, 1, genesis, func(i int, b *core.BlockGen) {
 		// Transfer from account[0] to account[1]
 		//    value: 1000 wei
 		//    fee:   0 wei
 		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
 		b.AddTx(tx)
 		target = tx.Hash()
-	}))
+	})
+	defer backend.chain.Stop()
+	api := NewAPI(backend)
 	result, err := api.TraceTransaction(context.Background(), target, nil)
 	if err != nil {
 		t.Errorf("Failed to trace transaction %v", err)
@@ -379,13 +390,15 @@ func TestTraceBlock(t *testing.T) {
 		}}
 	genBlocks := 10
 	signer := types.HomesteadSigner{}
-	api := NewAPI(newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
+	backend := newTestBackend(t, genBlocks, genesis, func(i int, b *core.BlockGen) {
 		// Transfer from account[0] to account[1]
 		//    value: 1000 wei
 		//    fee:   0 wei
 		tx, _ := types.SignTx(types.NewTransaction(uint64(i), accounts[1].addr, big.NewInt(1000), params.TxGas, b.BaseFee(), nil), signer, accounts[0].key)
 		b.AddTx(tx)
-	}))
+	})
+	defer backend.chain.Stop()
+	api := NewAPI(backend)
 
 	var testSuite = []struct {
 		blockNumber rpc.BlockNumber
diff --git a/eth/tracers/internal/tracetest/calltrace_test.go b/eth/tracers/internal/tracetest/calltrace_test.go
index 507d29efc6..36768d765e 100644
--- a/eth/tracers/internal/tracetest/calltrace_test.go
+++ b/eth/tracers/internal/tracetest/calltrace_test.go
@@ -138,7 +138,7 @@ func testCallTracer(tracerName string, dirPath string, t *testing.T) {
 			if _, err = st.TransitionDb(common.Address{}); err != nil {
 				t.Fatalf("failed to execute transaction: %v", err)
 			}
-			// Retrieve the trace result and compare against the etalon
+			// Retrieve the trace result and compare against the expected.
 			res, err := tracer.GetResult()
 			if err != nil {
 				t.Fatalf("failed to retrieve trace result: %v", err)
@@ -291,7 +291,7 @@ func TestZeroValueToNotExitCall(t *testing.T) {
 	if _, err = st.TransitionDb(common.Address{}); err != nil {
 		t.Fatalf("failed to execute transaction: %v", err)
 	}
-	// Retrieve the trace result and compare against the etalon
+	// Retrieve the trace result and compare against the expected.
 	res, err := tracer.GetResult()
 	if err != nil {
 		t.Fatalf("failed to retrieve trace result: %v", err)
@@ -373,7 +373,7 @@ func testContractTracer(tracerName string, dirPath string, t *testing.T) {
 			if _, err = st.TransitionDb(common.Address{}); err != nil {
 				t.Fatalf("failed to execute transaction: %v", err)
 			}
-			// Retrieve the trace result and compare against the etalon
+			// Retrieve the trace result and compare against the expected.
 			res, err := tracer.GetResult()
 			if err != nil {
 				t.Fatalf("failed to retrieve trace result: %v", err)
diff --git a/eth/tracers/internal/tracetest/prestate_test.go b/eth/tracers/internal/tracetest/prestate_test.go
index ebf7d27105..74cbf3d931 100644
--- a/eth/tracers/internal/tracetest/prestate_test.go
+++ b/eth/tracers/internal/tracetest/prestate_test.go
@@ -122,7 +122,7 @@ func testPrestateDiffTracer(tracerName string, dirPath string, t *testing.T, typ
 			if _, err = st.TransitionDb(common.Address{}); err != nil {
 				t.Fatalf("failed to execute transaction: %v", err)
 			}
-			// Retrieve the trace result and compare against the etalon
+			// Retrieve the trace result and compare against the expected.
 			res, err := tracer.GetResult()
 			if err != nil {
 				t.Fatalf("failed to retrieve trace result: %v", err)
diff --git a/eth/tracers/internal/tracetest/util.go b/eth/tracers/internal/tracetest/util.go
index a3d435a38f..64601b35fd 100644
--- a/eth/tracers/internal/tracetest/util.go
+++ b/eth/tracers/internal/tracetest/util.go
@@ -6,7 +6,7 @@ import (
 	"strings"
 	"unicode"
 
-	// Force-load native and js pacakges, to trigger registration
+	// Force-load native and js packages, to trigger registration
 	_ "github.com/XinFinOrg/XDPoSChain/eth/tracers/js"
 	_ "github.com/XinFinOrg/XDPoSChain/eth/tracers/native"
 )