remove logic for handling down peers

ref tikv#5568

Signed-off-by: Wenbo Zhang <[email protected]>

server/schedule/checker/rule_checker.go

@@ -201,10 +201,9 @@ func (c *RuleChecker) replaceUnexpectRulePeer(region *core.RegionInfo, rf *place
 		return nil, errNoStoreToReplace
 	}
 	newPeer := &metapb.Peer{StoreId: store, Role: rf.Rule.Role.MetaPeerRole(), IsWitness: rf.Rule.IsWitness}
-	leaderID := region.GetLeader().GetId()
 	//  pick the smallest leader store to avoid the Offline store be snapshot generator bottleneck.
 	var newLeader *metapb.Peer
-	if leaderID == peer.GetId() {
+	if region.GetLeader().GetId() == peer.GetId() {
 		minCount := uint64(math.MaxUint64)
 		for _, p := range region.GetPeers() {
 			count := c.record.getOfflineLeaderCount(p.GetStoreId())
@@ -224,27 +223,11 @@ func (c *RuleChecker) replaceUnexpectRulePeer(region *core.RegionInfo, rf *place
 		}
 	}
 
-	var witness *metapb.Peer
-	for _, witness = range region.GetWitnesses() {
-		if witness.StoreId != peer.StoreId && witness.Id != leaderID {
-			break
-		}
-	}
-
 	createOp := func() (*operator.Operator, error) {
 		if newLeader != nil && newLeader.GetId() != peer.GetId() {
 			return operator.CreateReplaceLeaderPeerOperator("replace-rule-"+status+"-leader-peer", c.cluster, region, operator.OpReplica, peer.StoreId, newPeer, newLeader)
 		}
-		/* TODO: enable this after the pr balance witness merged
-		if newPeer.IsWitness {
-			return operator.CreateMoveWitnessOperator("replace-rule-"+status+"-witness-peer", c.cluster, region, peer.StoreId, newPeer.StoreId, operator.OpWitness)
-		}
-		*/
-		if witness == nil {
-			return operator.CreateMovePeerOperator("replace-rule-"+status+"-peer", c.cluster, region, operator.OpReplica, peer.StoreId, newPeer)
-		}
-		newPeer.IsWitness = true
-		return operator.CreateMovePeerAndPromoteWitnessToVoterOperator("replace-rule-"+status+"-peer", c.cluster, region, operator.OpReplica, peer.StoreId, newPeer, witness.StoreId)
+		return operator.CreateMovePeerOperator("replace-rule-"+status+"-peer", c.cluster, region, operator.OpReplica, peer.StoreId, newPeer)
 	}
 	op, err := createOp()
 	if err != nil {

server/schedule/checker/rule_checker_test.go

@@ -368,45 +368,6 @@ func (suite *ruleCheckerTestSuite) TestFixRuleWitness3() {
 }
 
 func (suite *ruleCheckerTestSuite) TestFixRuleWitness4() {
-	suite.cluster.AddLabelsStore(1, 1, map[string]string{"A": "leader"})
-	suite.cluster.AddLabelsStore(2, 1, map[string]string{"B": "voter"})
-	suite.cluster.AddLabelsStore(3, 1, map[string]string{"C": "voter"})
-	suite.cluster.AddLabelsStore(4, 1, map[string]string{"D": "voter"})
-	suite.cluster.AddLeaderRegion(1, 1, 2, 3)
-
-	suite.cluster.SetStoreDown(2)
-	r := suite.cluster.GetRegion(1)
-	// set peer2 to down
-	r = r.Clone(core.WithDownPeers([]*pdpb.PeerStats{{Peer: r.GetStorePeer(2), DownSeconds: 60000}}))
-	// set peer3 to witness
-	r = r.Clone(core.WithWitnesses([]*metapb.Peer{r.GetPeer(3)}))
-
-	suite.ruleManager.SetRule(&placement.Rule{
-		GroupID: "pd",
-		ID:      "default",
-		Role:    placement.Voter,
-		Count:   2,
-	})
-	suite.ruleManager.SetRule(&placement.Rule{
-		GroupID:   "pd",
-		ID:        "r1",
-		Role:      placement.Voter,
-		Count:     1,
-		IsWitness: true,
-	})
-
-	op := suite.rc.Check(r)
-
-	suite.NotNil(op)
-	suite.Equal("replace-rule-down-peer", op.Desc())
-	suite.Equal(uint64(4), op.Step(0).(operator.AddLearner).ToStore)
-	suite.Equal(uint64(4), op.Step(1).(operator.PromoteLearner).ToStore)
-	suite.Equal(uint64(2), op.Step(2).(operator.RemovePeer).FromStore)
-	suite.Equal(uint64(3), op.Step(3).(operator.RemovePeer).FromStore)
-	suite.Equal(uint64(3), op.Step(4).(operator.AddLearner).ToStore)
-}
-
-func (suite *ruleCheckerTestSuite) TestFixRuleWitness5() {
 	suite.cluster.AddLabelsStore(1, 1, map[string]string{"A": "leader"})
 	suite.cluster.AddLabelsStore(2, 1, map[string]string{"B": "voter"})
 	suite.cluster.AddLabelsStore(3, 1, map[string]string{"C": "voter"})

server/schedule/operator/create_operator.go

@@ -302,12 +302,3 @@ func CreateNonWitnessPeerOperator(desc string, ci ClusterInformer, region *core.
 	brief := fmt.Sprintf("promote to non-witness: region %v peer %v on store %v", region.GetID(), peer.Id, peer.StoreId)
 	return NewOperator(desc, brief, region.GetID(), region.GetRegionEpoch(), OpRegion, region.GetApproximateSize(), BecomeNonWitness{StoreID: peer.StoreId, PeerID: peer.Id}), nil
 }
-
-// CreateMovePeerAndPromoteWitnessToVoterOperator creates an operator that replaces an old peer with a new peer, and promote a witness to voter.
-func CreateMovePeerAndPromoteWitnessToVoterOperator(desc string, ci ClusterInformer, region *core.RegionInfo, kind OpKind, oldStore uint64, peer *metapb.Peer, witnessStore uint64) (*Operator, error) {
-	return NewBuilder(desc, ci, region).
-		RemovePeer(oldStore).
-		AddPeer(peer).
-		BecomeNonWitness(witnessStore).
-		Build(kind)
-}