diff --git a/store/mockstore/unistore/tikv/server.go b/store/mockstore/unistore/tikv/server.go
index 14260ab991e94..f7779b51a8d69 100644
--- a/store/mockstore/unistore/tikv/server.go
+++ b/store/mockstore/unistore/tikv/server.go
@@ -158,7 +158,7 @@ func (req *requestCtx) finish() {
 	}
 }
 
-// KvGet implements implements the tikvpb.TikvServer interface.
+// KvGet implements the tikvpb.TikvServer interface.
 func (svr *Server) KvGet(ctx context.Context, req *kvrpcpb.GetRequest) (*kvrpcpb.GetResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvGet")
 	if err != nil {
@@ -175,7 +175,7 @@ func (svr *Server) KvGet(ctx context.Context, req *kvrpcpb.GetRequest) (*kvrpcpb
 	}, nil
 }
 
-// KvScan implements implements the tikvpb.TikvServer interface.
+// KvScan implements the tikvpb.TikvServer interface.
 func (svr *Server) KvScan(ctx context.Context, req *kvrpcpb.ScanRequest) (*kvrpcpb.ScanResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvScan")
 	if err != nil {
@@ -191,7 +191,7 @@ func (svr *Server) KvScan(ctx context.Context, req *kvrpcpb.ScanRequest) (*kvrpc
 	}, nil
 }
 
-// KvPessimisticLock implements implements the tikvpb.TikvServer interface.
+// KvPessimisticLock implements the tikvpb.TikvServer interface.
 func (svr *Server) KvPessimisticLock(ctx context.Context, req *kvrpcpb.PessimisticLockRequest) (*kvrpcpb.PessimisticLockResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "PessimisticLock")
 	if err != nil {
@@ -252,7 +252,7 @@ func (svr *Server) KvPessimisticLock(ctx context.Context, req *kvrpcpb.Pessimist
 	return resp, nil
 }
 
-// KVPessimisticRollback implements implements the tikvpb.TikvServer interface.
+// KVPessimisticRollback implements the tikvpb.TikvServer interface.
 func (svr *Server) KVPessimisticRollback(ctx context.Context, req *kvrpcpb.PessimisticRollbackRequest) (*kvrpcpb.PessimisticRollbackResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "PessimisticRollback")
 	if err != nil {
@@ -268,7 +268,7 @@ func (svr *Server) KVPessimisticRollback(ctx context.Context, req *kvrpcpb.Pessi
 	return resp, nil
 }
 
-// KvTxnHeartBeat implements implements the tikvpb.TikvServer interface.
+// KvTxnHeartBeat implements the tikvpb.TikvServer interface.
 func (svr *Server) KvTxnHeartBeat(ctx context.Context, req *kvrpcpb.TxnHeartBeatRequest) (*kvrpcpb.TxnHeartBeatResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "TxnHeartBeat")
 	if err != nil {
@@ -284,7 +284,7 @@ func (svr *Server) KvTxnHeartBeat(ctx context.Context, req *kvrpcpb.TxnHeartBeat
 	return resp, nil
 }
 
-// KvCheckTxnStatus implements implements the tikvpb.TikvServer interface.
+// KvCheckTxnStatus implements the tikvpb.TikvServer interface.
 func (svr *Server) KvCheckTxnStatus(ctx context.Context, req *kvrpcpb.CheckTxnStatusRequest) (*kvrpcpb.CheckTxnStatusResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvCheckTxnStatus")
 	if err != nil {
@@ -309,7 +309,7 @@ func (svr *Server) KvCheckTxnStatus(ctx context.Context, req *kvrpcpb.CheckTxnSt
 	return resp, nil
 }
 
-// KvCheckSecondaryLocks implements implements the tikvpb.TikvServer interface.
+// KvCheckSecondaryLocks implements the tikvpb.TikvServer interface.
 func (svr *Server) KvCheckSecondaryLocks(ctx context.Context, req *kvrpcpb.CheckSecondaryLocksRequest) (*kvrpcpb.CheckSecondaryLocksResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvCheckSecondaryLocks")
 	if err != nil {
@@ -330,7 +330,7 @@ func (svr *Server) KvCheckSecondaryLocks(ctx context.Context, req *kvrpcpb.Check
 	return resp, nil
 }
 
-// KvPrewrite implements implements the tikvpb.TikvServer interface.
+// KvPrewrite implements the tikvpb.TikvServer interface.
 func (svr *Server) KvPrewrite(ctx context.Context, req *kvrpcpb.PrewriteRequest) (*kvrpcpb.PrewriteResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvPrewrite")
 	if err != nil {
@@ -352,7 +352,7 @@ func (svr *Server) KvPrewrite(ctx context.Context, req *kvrpcpb.PrewriteRequest)
 	return resp, nil
 }
 
-// KvCommit implements implements the tikvpb.TikvServer interface.
+// KvCommit implements the tikvpb.TikvServer interface.
 func (svr *Server) KvCommit(ctx context.Context, req *kvrpcpb.CommitRequest) (*kvrpcpb.CommitResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvCommit")
 	if err != nil {
@@ -370,19 +370,19 @@ func (svr *Server) KvCommit(ctx context.Context, req *kvrpcpb.CommitRequest) (*k
 	return resp, nil
 }
 
-// RawGetKeyTTL implements implements the tikvpb.TikvServer interface.
+// RawGetKeyTTL implements the tikvpb.TikvServer interface.
 func (svr *Server) RawGetKeyTTL(ctx context.Context, req *kvrpcpb.RawGetKeyTTLRequest) (*kvrpcpb.RawGetKeyTTLResponse, error) {
 	// TODO
 	return &kvrpcpb.RawGetKeyTTLResponse{}, nil
 }
 
-// KvImport implements implements the tikvpb.TikvServer interface.
+// KvImport implements the tikvpb.TikvServer interface.
 func (svr *Server) KvImport(context.Context, *kvrpcpb.ImportRequest) (*kvrpcpb.ImportResponse, error) {
 	// TODO
 	return &kvrpcpb.ImportResponse{}, nil
 }
 
-// KvCleanup implements implements the tikvpb.TikvServer interface.
+// KvCleanup implements the tikvpb.TikvServer interface.
 func (svr *Server) KvCleanup(ctx context.Context, req *kvrpcpb.CleanupRequest) (*kvrpcpb.CleanupResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvCleanup")
 	if err != nil {
@@ -403,7 +403,7 @@ func (svr *Server) KvCleanup(ctx context.Context, req *kvrpcpb.CleanupRequest) (
 	return resp, nil
 }
 
-// KvBatchGet implements implements the tikvpb.TikvServer interface.
+// KvBatchGet implements the tikvpb.TikvServer interface.
 func (svr *Server) KvBatchGet(ctx context.Context, req *kvrpcpb.BatchGetRequest) (*kvrpcpb.BatchGetResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvBatchGet")
 	if err != nil {
@@ -419,7 +419,7 @@ func (svr *Server) KvBatchGet(ctx context.Context, req *kvrpcpb.BatchGetRequest)
 	}, nil
 }
 
-// KvBatchRollback implements implements the tikvpb.TikvServer interface.
+// KvBatchRollback implements the tikvpb.TikvServer interface.
 func (svr *Server) KvBatchRollback(ctx context.Context, req *kvrpcpb.BatchRollbackRequest) (*kvrpcpb.BatchRollbackResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvBatchRollback")
 	if err != nil {
@@ -435,7 +435,7 @@ func (svr *Server) KvBatchRollback(ctx context.Context, req *kvrpcpb.BatchRollba
 	return resp, nil
 }
 
-// KvScanLock implements implements the tikvpb.TikvServer interface.
+// KvScanLock implements the tikvpb.TikvServer interface.
 func (svr *Server) KvScanLock(ctx context.Context, req *kvrpcpb.ScanLockRequest) (*kvrpcpb.ScanLockResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvScanLock")
 	if err != nil {
@@ -450,7 +450,7 @@ func (svr *Server) KvScanLock(ctx context.Context, req *kvrpcpb.ScanLockRequest)
 	return &kvrpcpb.ScanLockResponse{Error: convertToKeyError(err), Locks: locks}, nil
 }
 
-// KvResolveLock implements implements the tikvpb.TikvServer interface.
+// KvResolveLock implements the tikvpb.TikvServer interface.
 func (svr *Server) KvResolveLock(ctx context.Context, req *kvrpcpb.ResolveLockRequest) (*kvrpcpb.ResolveLockResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvResolveLock")
 	if err != nil {
@@ -478,7 +478,7 @@ func (svr *Server) KvResolveLock(ctx context.Context, req *kvrpcpb.ResolveLockRe
 	return resp, nil
 }
 
-// KvGC implements implements the tikvpb.TikvServer interface.
+// KvGC implements the tikvpb.TikvServer interface.
 func (svr *Server) KvGC(ctx context.Context, req *kvrpcpb.GCRequest) (*kvrpcpb.GCResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvGC")
 	if err != nil {
@@ -489,7 +489,7 @@ func (svr *Server) KvGC(ctx context.Context, req *kvrpcpb.GCRequest) (*kvrpcpb.G
 	return &kvrpcpb.GCResponse{}, nil
 }
 
-// KvDeleteRange implements implements the tikvpb.TikvServer interface.
+// KvDeleteRange implements the tikvpb.TikvServer interface.
 func (svr *Server) KvDeleteRange(ctx context.Context, req *kvrpcpb.DeleteRangeRequest) (*kvrpcpb.DeleteRangeResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "KvDeleteRange")
 	if err != nil {
@@ -508,54 +508,54 @@ func (svr *Server) KvDeleteRange(ctx context.Context, req *kvrpcpb.DeleteRangeRe
 
 // RawKV commands.
 
-// RawGet implements implements the tikvpb.TikvServer interface.
+// RawGet implements the tikvpb.TikvServer interface.
 func (svr *Server) RawGet(context.Context, *kvrpcpb.RawGetRequest) (*kvrpcpb.RawGetResponse, error) {
 	return &kvrpcpb.RawGetResponse{}, nil
 }
 
-// RawPut implements implements the tikvpb.TikvServer interface.
+// RawPut implements the tikvpb.TikvServer interface.
 func (svr *Server) RawPut(context.Context, *kvrpcpb.RawPutRequest) (*kvrpcpb.RawPutResponse, error) {
 	return &kvrpcpb.RawPutResponse{}, nil
 }
 
-// RawDelete implements implements the tikvpb.TikvServer interface.
+// RawDelete implements the tikvpb.TikvServer interface.
 func (svr *Server) RawDelete(context.Context, *kvrpcpb.RawDeleteRequest) (*kvrpcpb.RawDeleteResponse, error) {
 	return &kvrpcpb.RawDeleteResponse{}, nil
 }
 
-// RawScan implements implements the tikvpb.TikvServer interface.
+// RawScan implements the tikvpb.TikvServer interface.
 func (svr *Server) RawScan(context.Context, *kvrpcpb.RawScanRequest) (*kvrpcpb.RawScanResponse, error) {
 	return &kvrpcpb.RawScanResponse{}, nil
 }
 
-// RawBatchDelete implements implements the tikvpb.TikvServer interface.
+// RawBatchDelete implements the tikvpb.TikvServer interface.
 func (svr *Server) RawBatchDelete(context.Context, *kvrpcpb.RawBatchDeleteRequest) (*kvrpcpb.RawBatchDeleteResponse, error) {
 	return &kvrpcpb.RawBatchDeleteResponse{}, nil
 }
 
-// RawBatchGet implements implements the tikvpb.TikvServer interface.
+// RawBatchGet implements the tikvpb.TikvServer interface.
 func (svr *Server) RawBatchGet(context.Context, *kvrpcpb.RawBatchGetRequest) (*kvrpcpb.RawBatchGetResponse, error) {
 	return &kvrpcpb.RawBatchGetResponse{}, nil
 }
 
-// RawBatchPut implements implements the tikvpb.TikvServer interface.
+// RawBatchPut implements the tikvpb.TikvServer interface.
 func (svr *Server) RawBatchPut(context.Context, *kvrpcpb.RawBatchPutRequest) (*kvrpcpb.RawBatchPutResponse, error) {
 	return &kvrpcpb.RawBatchPutResponse{}, nil
 }
 
-// RawBatchScan implements implements the tikvpb.TikvServer interface.
+// RawBatchScan implements the tikvpb.TikvServer interface.
 func (svr *Server) RawBatchScan(context.Context, *kvrpcpb.RawBatchScanRequest) (*kvrpcpb.RawBatchScanResponse, error) {
 	return &kvrpcpb.RawBatchScanResponse{}, nil
 }
 
-// RawDeleteRange implements implements the tikvpb.TikvServer interface.
+// RawDeleteRange implements the tikvpb.TikvServer interface.
 func (svr *Server) RawDeleteRange(context.Context, *kvrpcpb.RawDeleteRangeRequest) (*kvrpcpb.RawDeleteRangeResponse, error) {
 	return &kvrpcpb.RawDeleteRangeResponse{}, nil
 }
 
 // SQL push down commands.
 
-// Coprocessor implements implements the tikvpb.TikvServer interface.
+// Coprocessor implements the tikvpb.TikvServer interface.
 func (svr *Server) Coprocessor(_ context.Context, req *coprocessor.Request) (*coprocessor.Response, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "Coprocessor")
 	if err != nil {
@@ -568,7 +568,7 @@ func (svr *Server) Coprocessor(_ context.Context, req *coprocessor.Request) (*co
 	return cophandler.HandleCopRequest(reqCtx.getDBReader(), svr.mvccStore.lockStore, req), nil
 }
 
-// CoprocessorStream implements implements the tikvpb.TikvServer interface.
+// CoprocessorStream implements the tikvpb.TikvServer interface.
 func (svr *Server) CoprocessorStream(*coprocessor.Request, tikvpb.Tikv_CoprocessorStreamServer) error {
 	// TODO
 	return nil
@@ -584,7 +584,7 @@ func (regionError *RegionError) Error() string {
 	return regionError.err.Message
 }
 
-// BatchCoprocessor implements implements the tikvpb.TikvServer interface.
+// BatchCoprocessor implements the tikvpb.TikvServer interface.
 func (svr *Server) BatchCoprocessor(req *coprocessor.BatchRequest, batchCopServer tikvpb.Tikv_BatchCoprocessorServer) error {
 	reqCtxs := make([]*requestCtx, 0, len(req.Regions))
 	defer func() {
@@ -628,7 +628,7 @@ func (svr *Server) BatchCoprocessor(req *coprocessor.BatchRequest, batchCopServe
 	return nil
 }
 
-// RawCoprocessor implements implements the tikvpb.TikvServer interface.
+// RawCoprocessor implements the tikvpb.TikvServer interface.
 func (svr *Server) RawCoprocessor(context.Context, *kvrpcpb.RawCoprocessorRequest) (*kvrpcpb.RawCoprocessorResponse, error) {
 	panic("unimplemented")
 }
@@ -710,7 +710,7 @@ func (svr *Server) executeMPPDispatch(ctx context.Context, req *mpp.DispatchTask
 	return nil
 }
 
-// DispatchMPPTaskWithStoreID implements implements the tikvpb.TikvServer interface.
+// DispatchMPPTaskWithStoreID implements the tikvpb.TikvServer interface.
 func (svr *Server) DispatchMPPTaskWithStoreID(ctx context.Context, req *mpp.DispatchTaskRequest, storeID uint64) (*mpp.DispatchTaskResponse, error) {
 	mppHandler, err := svr.CreateMPPTaskHandler(req.Meta, storeID)
 	if err != nil {
@@ -728,12 +728,12 @@ func (svr *Server) DispatchMPPTaskWithStoreID(ctx context.Context, req *mpp.Disp
 	return resp, nil
 }
 
-// CancelMPPTask implements implements the tikvpb.TikvServer interface.
+// CancelMPPTask implements the tikvpb.TikvServer interface.
 func (svr *Server) CancelMPPTask(_ context.Context, _ *mpp.CancelTaskRequest) (*mpp.CancelTaskResponse, error) {
 	panic("todo")
 }
 
-// GetMPPTaskHandler implements implements the tikvpb.TikvServer interface.
+// GetMPPTaskHandler implements the tikvpb.TikvServer interface.
 func (svr *Server) GetMPPTaskHandler(taskID int64, storeID uint64) (*cophandler.MPPTaskHandler, error) {
 	if mrm, ok := svr.regionManager.(*MockRegionManager); ok {
 		set := mrm.getMPPTaskSet(storeID)
@@ -750,7 +750,7 @@ func (svr *Server) GetMPPTaskHandler(taskID int64, storeID uint64) (*cophandler.
 	return nil, errors.New("Only mock region mgr supports get mpp task")
 }
 
-// RemoveMPPTaskHandler implements implements the tikvpb.TikvServer interface.
+// RemoveMPPTaskHandler implements the tikvpb.TikvServer interface.
 func (svr *Server) RemoveMPPTaskHandler(taskID int64, storeID uint64) error {
 	if mrm, ok := svr.regionManager.(*MockRegionManager); ok {
 		err := mrm.removeMPPTaskHandler(taskID, storeID)
@@ -759,7 +759,7 @@ func (svr *Server) RemoveMPPTaskHandler(taskID int64, storeID uint64) error {
 	return errors.New("Only mock region mgr supports remove mpp task")
 }
 
-// CreateMPPTaskHandler implements implements the tikvpb.TikvServer interface.
+// CreateMPPTaskHandler implements the tikvpb.TikvServer interface.
 func (svr *Server) CreateMPPTaskHandler(meta *mpp.TaskMeta, storeID uint64) (*cophandler.MPPTaskHandler, error) {
 	if mrm, ok := svr.regionManager.(*MockRegionManager); ok {
 		set := mrm.getMPPTaskSet(storeID)
@@ -782,12 +782,12 @@ func (svr *Server) CreateMPPTaskHandler(meta *mpp.TaskMeta, storeID uint64) (*co
 	return nil, errors.New("Only mock region mgr supports get mpp task")
 }
 
-// EstablishMPPConnection implements implements the tikvpb.TikvServer interface.
+// EstablishMPPConnection implements the tikvpb.TikvServer interface.
 func (svr *Server) EstablishMPPConnection(*mpp.EstablishMPPConnectionRequest, tikvpb.Tikv_EstablishMPPConnectionServer) error {
 	panic("todo")
 }
 
-// EstablishMPPConnectionWithStoreID implements implements the tikvpb.TikvServer interface.
+// EstablishMPPConnectionWithStoreID implements the tikvpb.TikvServer interface.
 func (svr *Server) EstablishMPPConnectionWithStoreID(req *mpp.EstablishMPPConnectionRequest, server tikvpb.Tikv_EstablishMPPConnectionServer, storeID uint64) error {
 	var (
 		mppHandler *cophandler.MPPTaskHandler
@@ -840,24 +840,24 @@ func (svr *Server) EstablishMPPConnectionWithStoreID(req *mpp.EstablishMPPConnec
 
 // Raft commands (tikv <-> tikv).
 
-// Raft implements implements the tikvpb.TikvServer interface.
+// Raft implements the tikvpb.TikvServer interface.
 func (svr *Server) Raft(stream tikvpb.Tikv_RaftServer) error {
 	return svr.innerServer.Raft(stream)
 }
 
-// Snapshot implements implements the tikvpb.TikvServer interface.
+// Snapshot implements the tikvpb.TikvServer interface.
 func (svr *Server) Snapshot(stream tikvpb.Tikv_SnapshotServer) error {
 	return svr.innerServer.Snapshot(stream)
 }
 
-// BatchRaft implements implements the tikvpb.TikvServer interface.
+// BatchRaft implements the tikvpb.TikvServer interface.
 func (svr *Server) BatchRaft(stream tikvpb.Tikv_BatchRaftServer) error {
 	return svr.innerServer.BatchRaft(stream)
 }
 
 // Region commands.
 
-// SplitRegion implements implements the tikvpb.TikvServer interface.
+// SplitRegion implements the tikvpb.TikvServer interface.
 func (svr *Server) SplitRegion(ctx context.Context, req *kvrpcpb.SplitRegionRequest) (*kvrpcpb.SplitRegionResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "SplitRegion")
 	if err != nil {
@@ -872,7 +872,7 @@ func (svr *Server) Compact(ctx context.Context, req *kvrpcpb.CompactRequest) (*k
 	panic("unimplemented")
 }
 
-// ReadIndex implements implements the tikvpb.TikvServer interface.
+// ReadIndex implements the tikvpb.TikvServer interface.
 func (svr *Server) ReadIndex(context.Context, *kvrpcpb.ReadIndexRequest) (*kvrpcpb.ReadIndexResponse, error) {
 	// TODO:
 	return &kvrpcpb.ReadIndexResponse{}, nil
@@ -880,7 +880,7 @@ func (svr *Server) ReadIndex(context.Context, *kvrpcpb.ReadIndexRequest) (*kvrpc
 
 // transaction debugger commands.
 
-// MvccGetByKey implements implements the tikvpb.TikvServer interface.
+// MvccGetByKey implements the tikvpb.TikvServer interface.
 func (svr *Server) MvccGetByKey(ctx context.Context, req *kvrpcpb.MvccGetByKeyRequest) (*kvrpcpb.MvccGetByKeyResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "MvccGetByKey")
 	if err != nil {
@@ -899,7 +899,7 @@ func (svr *Server) MvccGetByKey(ctx context.Context, req *kvrpcpb.MvccGetByKeyRe
 	return resp, nil
 }
 
-// MvccGetByStartTs implements implements the tikvpb.TikvServer interface.
+// MvccGetByStartTs implements the tikvpb.TikvServer interface.
 func (svr *Server) MvccGetByStartTs(ctx context.Context, req *kvrpcpb.MvccGetByStartTsRequest) (*kvrpcpb.MvccGetByStartTsResponse, error) {
 	reqCtx, err := newRequestCtx(svr, req.Context, "MvccGetByStartTs")
 	if err != nil {
@@ -919,7 +919,7 @@ func (svr *Server) MvccGetByStartTs(ctx context.Context, req *kvrpcpb.MvccGetByS
 	return resp, nil
 }
 
-// UnsafeDestroyRange implements implements the tikvpb.TikvServer interface.
+// UnsafeDestroyRange implements the tikvpb.TikvServer interface.
 func (svr *Server) UnsafeDestroyRange(ctx context.Context, req *kvrpcpb.UnsafeDestroyRangeRequest) (*kvrpcpb.UnsafeDestroyRangeResponse, error) {
 	start, end := req.GetStartKey(), req.GetEndKey()
 	svr.mvccStore.DeleteFileInRange(start, end)
@@ -959,32 +959,32 @@ func (svr *Server) Detect(stream deadlockPb.Deadlock_DetectServer) error {
 	return nil
 }
 
-// CheckLockObserver implements implements the tikvpb.TikvServer interface.
+// CheckLockObserver implements the tikvpb.TikvServer interface.
 func (svr *Server) CheckLockObserver(context.Context, *kvrpcpb.CheckLockObserverRequest) (*kvrpcpb.CheckLockObserverResponse, error) {
 	// TODO: implement Observer
 	return &kvrpcpb.CheckLockObserverResponse{IsClean: true}, nil
 }
 
-// PhysicalScanLock implements implements the tikvpb.TikvServer interface.
+// PhysicalScanLock implements the tikvpb.TikvServer interface.
 func (svr *Server) PhysicalScanLock(ctx context.Context, req *kvrpcpb.PhysicalScanLockRequest) (*kvrpcpb.PhysicalScanLockResponse, error) {
 	resp := &kvrpcpb.PhysicalScanLockResponse{}
 	resp.Locks = svr.mvccStore.PhysicalScanLock(req.StartKey, req.MaxTs, int(req.Limit))
 	return resp, nil
 }
 
-// RegisterLockObserver implements implements the tikvpb.TikvServer interface.
+// RegisterLockObserver implements the tikvpb.TikvServer interface.
 func (svr *Server) RegisterLockObserver(context.Context, *kvrpcpb.RegisterLockObserverRequest) (*kvrpcpb.RegisterLockObserverResponse, error) {
 	// TODO: implement Observer
 	return &kvrpcpb.RegisterLockObserverResponse{}, nil
 }
 
-// RemoveLockObserver implements implements the tikvpb.TikvServer interface.
+// RemoveLockObserver implements the tikvpb.TikvServer interface.
 func (svr *Server) RemoveLockObserver(context.Context, *kvrpcpb.RemoveLockObserverRequest) (*kvrpcpb.RemoveLockObserverResponse, error) {
 	// TODO: implement Observer
 	return &kvrpcpb.RemoveLockObserverResponse{}, nil
 }
 
-// CheckLeader implements implements the tikvpb.TikvServer interface.
+// CheckLeader implements the tikvpb.TikvServer interface.
 func (svr *Server) CheckLeader(context.Context, *kvrpcpb.CheckLeaderRequest) (*kvrpcpb.CheckLeaderResponse, error) {
 	panic("unimplemented")
 }
@@ -1004,7 +1004,7 @@ func (svr *Server) GetLockWaitInfo(context.Context, *kvrpcpb.GetLockWaitInfoRequ
 	panic("unimplemented")
 }
 
-// RawChecksum implements implements the tikvpb.TikvServer interface.
+// RawChecksum implements the tikvpb.TikvServer interface.
 func (svr *Server) RawChecksum(context.Context, *kvrpcpb.RawChecksumRequest) (*kvrpcpb.RawChecksumResponse, error) {
 	panic("unimplemented")
 }