tikv: fix region cache do not filter the down peers (#17337)

go.mod

@@ -8,12 +8,12 @@ require (
 	github.com/danjacques/gofslock v0.0.0-20191023191349-0a45f885bc37
 	github.com/dgraph-io/ristretto v0.0.1
 	github.com/dgryski/go-farm v0.0.0-20190423205320-6a90982ecee2
-	github.com/go-sql-driver/mysql v1.4.1
+	github.com/go-sql-driver/mysql v1.5.0
 	github.com/gogo/protobuf v1.3.1
 	github.com/golang/protobuf v1.3.4
 	github.com/golang/snappy v0.0.1
 	github.com/google/btree v1.0.0
-	github.com/google/pprof v0.0.0-20190930153522-6ce02741cba3
+	github.com/google/pprof v0.0.0-20200407044318-7d83b28da2e9
 	github.com/google/uuid v1.1.1
 	github.com/gorilla/mux v1.7.3
 	github.com/grpc-ecosystem/go-grpc-middleware v1.0.1-0.20190118093823-f849b5445de4
@@ -22,30 +22,29 @@ require (
 	github.com/ngaut/sync2 v0.0.0-20141008032647-7a24ed77b2ef
 	github.com/opentracing/basictracer-go v1.0.0
 	github.com/opentracing/opentracing-go v1.1.0
-	github.com/pingcap/br v0.0.0-20200426093517-dd11ae28b885
+	github.com/pingcap/br v0.0.0-20200521085655-53201addd4ad
 	github.com/pingcap/check v0.0.0-20200212061837-5e12011dc712
 	github.com/pingcap/errors v0.11.5-0.20190809092503-95897b64e011
-	github.com/pingcap/failpoint v0.0.0-20200210140405-f8f9fb234798
+	github.com/pingcap/failpoint v0.0.0-20200506114213-c17f16071c53
 	github.com/pingcap/fn v0.0.0-20191016082858-07623b84a47d
 	github.com/pingcap/goleveldb v0.0.0-20191226122134-f82aafb29989
-	github.com/pingcap/kvproto v0.0.0-20200428135407-0f5ffe459677
+	github.com/pingcap/kvproto v0.0.0-20200518112156-d4aeb467de29
 	github.com/pingcap/log v0.0.0-20200511115504-543df19646ad
 	github.com/pingcap/parser v0.0.0-20200521064712-8dc0fb6ce6f4
-	github.com/pingcap/pd/v4 v4.0.0-rc.1.0.20200422143320-428acd53eba2
+	github.com/pingcap/pd/v4 v4.0.0-rc.2.0.20200520083007-2c251bd8f181
 	github.com/pingcap/sysutil v0.0.0-20200408114249-ed3bd6f7fdb1
-	github.com/pingcap/tidb-tools v4.0.0-rc.1.0.20200421113014-507d2bb3a15e+incompatible
+	github.com/pingcap/tidb-tools v4.0.0-rc.1.0.20200514040632-f76b3e428e19+incompatible
 	github.com/pingcap/tipb v0.0.0-20200417094153-7316d94df1ee
-	github.com/prometheus/client_golang v1.0.0
-	github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4
-	github.com/prometheus/common v0.4.1
+	github.com/prometheus/client_golang v1.5.1
+	github.com/prometheus/client_model v0.2.0
+	github.com/prometheus/common v0.9.1
 	github.com/shirou/gopsutil v2.19.10+incompatible
-	github.com/sirupsen/logrus v1.4.2
+	github.com/sirupsen/logrus v1.6.0
 	github.com/soheilhy/cmux v0.1.4
 	github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72
 	github.com/tiancaiamao/appdash v0.0.0-20181126055449-889f96f722a2
 	github.com/uber-go/atomic v1.3.2
 	github.com/uber/jaeger-client-go v2.22.1+incompatible
-	github.com/uber/jaeger-lib v2.2.0+incompatible // indirect
 	go.etcd.io/etcd v0.5.0-alpha.5.0.20191023171146-3cf2f69b5738
 	go.uber.org/atomic v1.6.0
 	go.uber.org/automaxprocs v1.2.0
@@ -55,7 +54,7 @@ require (
 	golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd
 	golang.org/x/text v0.3.2
 	golang.org/x/tools v0.0.0-20200325203130-f53864d0dba1
-	google.golang.org/grpc v1.25.1
+	google.golang.org/grpc v1.26.0
 	gopkg.in/natefinch/lumberjack.v2 v2.0.0
 	sourcegraph.com/sourcegraph/appdash v0.0.0-20180531100431-4c381bd170b4
 	sourcegraph.com/sourcegraph/appdash-data v0.0.0-20151005221446-73f23eafcf67

server/http_handler.go

@@ -591,25 +591,25 @@ type RegionFrameRange struct {
 func (t *tikvHandlerTool) getRegionsMeta(regionIDs []uint64) ([]RegionMeta, error) {
 	regions := make([]RegionMeta, len(regionIDs))
 	for i, regionID := range regionIDs {
-		meta, leader, err := t.RegionCache.PDClient().GetRegionByID(context.TODO(), regionID)
+		region, err := t.RegionCache.PDClient().GetRegionByID(context.TODO(), regionID)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
 
 		failpoint.Inject("errGetRegionByIDEmpty", func(val failpoint.Value) {
 			if val.(bool) {
-				meta = nil
+				region.Meta = nil
 			}
 		})
 
-		if meta == nil {
+		if region.Meta == nil {
 			return nil, errors.Errorf("region not found for regionID %q", regionID)
 		}
 		regions[i] = RegionMeta{
 			ID:          regionID,
-			Leader:      leader,
-			Peers:       meta.Peers,
-			RegionEpoch: meta.RegionEpoch,
+			Leader:      region.Leader,
+			Peers:       region.Meta.Peers,
+			RegionEpoch: region.Meta.RegionEpoch,
 		}
 
 	}

store/mockstore/mocktikv/pd.go

@@ -91,19 +91,19 @@ func (m *mockTSFuture) Wait() (int64, int64, error) {
 	return m.pdc.GetTS(m.ctx)
 }
 
-func (c *pdClient) GetRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *pdClient) GetRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	region, peer := c.cluster.GetRegionByKey(key)
-	return region, peer, nil
+	return &pd.Region{Meta: region, Leader: peer}, nil
 }
 
-func (c *pdClient) GetPrevRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *pdClient) GetPrevRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	region, peer := c.cluster.GetPrevRegionByKey(key)
-	return region, peer, nil
+	return &pd.Region{Meta: region, Leader: peer}, nil
 }
 
-func (c *pdClient) GetRegionByID(ctx context.Context, regionID uint64) (*metapb.Region, *metapb.Peer, error) {
+func (c *pdClient) GetRegionByID(ctx context.Context, regionID uint64) (*pd.Region, error) {
 	region, peer := c.cluster.GetRegionByID(regionID)
-	return region, peer, nil
+	return &pd.Region{Meta: region, Leader: peer}, nil
 }
 
 func (c *pdClient) ScanRegions(ctx context.Context, startKey []byte, endKey []byte, limit int) ([]*metapb.Region, []*metapb.Peer, error) {

store/tikv/pd_codec.go

@@ -28,23 +28,23 @@ type codecPDClient struct {
 
 // GetRegion encodes the key before send requests to pd-server and decodes the
 // returned StartKey && EndKey from pd-server.
-func (c *codecPDClient) GetRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *codecPDClient) GetRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	encodedKey := codec.EncodeBytes([]byte(nil), key)
-	region, peer, err := c.Client.GetRegion(ctx, encodedKey)
-	return processRegionResult(region, peer, err)
+	region, err := c.Client.GetRegion(ctx, encodedKey)
+	return processRegionResult(region, err)
 }
 
-func (c *codecPDClient) GetPrevRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *codecPDClient) GetPrevRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	encodedKey := codec.EncodeBytes([]byte(nil), key)
-	region, peer, err := c.Client.GetPrevRegion(ctx, encodedKey)
-	return processRegionResult(region, peer, err)
+	region, err := c.Client.GetPrevRegion(ctx, encodedKey)
+	return processRegionResult(region, err)
 }
 
 // GetRegionByID encodes the key before send requests to pd-server and decodes the
 // returned StartKey && EndKey from pd-server.
-func (c *codecPDClient) GetRegionByID(ctx context.Context, regionID uint64) (*metapb.Region, *metapb.Peer, error) {
-	region, peer, err := c.Client.GetRegionByID(ctx, regionID)
-	return processRegionResult(region, peer, err)
+func (c *codecPDClient) GetRegionByID(ctx context.Context, regionID uint64) (*pd.Region, error) {
+	region, err := c.Client.GetRegionByID(ctx, regionID)
+	return processRegionResult(region, err)
 }
 
 func (c *codecPDClient) ScanRegions(ctx context.Context, startKey []byte, endKey []byte, limit int) ([]*metapb.Region, []*metapb.Peer, error) {
@@ -68,18 +68,18 @@ func (c *codecPDClient) ScanRegions(ctx context.Context, startKey []byte, endKey
 	return regions, peers, nil
 }
 
-func processRegionResult(region *metapb.Region, peer *metapb.Peer, err error) (*metapb.Region, *metapb.Peer, error) {
+func processRegionResult(region *pd.Region, err error) (*pd.Region, error) {
 	if err != nil {
-		return nil, nil, errors.Trace(err)
+		return nil, errors.Trace(err)
 	}
-	if region == nil {
-		return nil, nil, nil
+	if region == nil || region.Meta == nil {
+		return nil, nil
 	}
-	err = decodeRegionMetaKeyInPlace(region)
+	err = decodeRegionMetaKeyInPlace(region.Meta)
 	if err != nil {
-		return nil, nil, errors.Trace(err)
+		return nil, errors.Trace(err)
 	}
-	return region, peer, nil
+	return region, nil
 }
 
 func decodeRegionMetaKeyInPlace(r *metapb.Region) error {

store/tikv/region_cache.go

@@ -850,6 +850,29 @@ func (c *RegionCache) getRegionByIDFromCache(regionID uint64) *Region {
 	return newestRegion
 }
 
+func filterUnavailablePeers(region *pd.Region) {
+	if len(region.DownPeers) == 0 {
+		return
+	}
+	new := region.Meta.Peers[:0]
+	for _, p := range region.Meta.Peers {
+		available := true
+		for _, downPeer := range region.DownPeers {
+			if p.Id == downPeer.Id && p.StoreId == downPeer.StoreId {
+				available = false
+				break
+			}
+		}
+		if available {
+			new = append(new, p)
+		}
+	}
+	for i := len(new); i < len(region.Meta.Peers); i++ {
+		region.Meta.Peers[i] = nil
+	}
+	region.Meta.Peers = new
+}
+
 // loadRegion loads region from pd client, and picks the first peer as leader.
 // If the given key is the end key of the region that you want, you may set the second argument to true. This is useful
 // when processing in reverse order.
@@ -863,13 +886,12 @@ func (c *RegionCache) loadRegion(bo *Backoffer, key []byte, isEndKey bool) (*Reg
 				return nil, errors.Trace(err)
 			}
 		}
-		var meta *metapb.Region
-		var leader *metapb.Peer
+		var reg *pd.Region
 		var err error
 		if searchPrev {
-			meta, leader, err = c.pdClient.GetPrevRegion(bo.ctx, key)
+			reg, err = c.pdClient.GetPrevRegion(bo.ctx, key)
 		} else {
-			meta, leader, err = c.pdClient.GetRegion(bo.ctx, key)
+			reg, err = c.pdClient.GetRegion(bo.ctx, key)
 		}
 		if err != nil {
 			tikvRegionCacheCounterWithGetRegionError.Inc()
@@ -880,21 +902,22 @@ func (c *RegionCache) loadRegion(bo *Backoffer, key []byte, isEndKey bool) (*Reg
 			backoffErr = errors.Errorf("loadRegion from PD failed, key: %q, err: %v", key, err)
 			continue
 		}
-		if meta == nil {
+		if reg == nil || reg.Meta == nil {
 			backoffErr = errors.Errorf("region not found for key %q", key)
 			continue
 		}
-		if len(meta.Peers) == 0 {
-			return nil, errors.New("receive Region with no peer")
+		filterUnavailablePeers(reg)
+		if len(reg.Meta.Peers) == 0 {
+			return nil, errors.New("receive Region with no available peer")
 		}
-		if isEndKey && !searchPrev && bytes.Equal(meta.StartKey, key) && len(meta.StartKey) != 0 {
+		if isEndKey && !searchPrev && bytes.Equal(reg.Meta.StartKey, key) && len(reg.Meta.StartKey) != 0 {
 			searchPrev = true
 			continue
 		}
-		region := &Region{meta: meta}
+		region := &Region{meta: reg.Meta}
 		region.init(c)
-		if leader != nil {
-			c.switchToPeer(region, leader.StoreId)
+		if reg.Leader != nil {
+			c.switchToPeer(region, reg.Leader.StoreId)
 		}
 		return region, nil
 	}
@@ -910,7 +933,7 @@ func (c *RegionCache) loadRegionByID(bo *Backoffer, regionID uint64) (*Region, e
 				return nil, errors.Trace(err)
 			}
 		}
-		meta, leader, err := c.pdClient.GetRegionByID(bo.ctx, regionID)
+		reg, err := c.pdClient.GetRegionByID(bo.ctx, regionID)
 		if err != nil {
 			tikvRegionCacheCounterWithGetRegionByIDError.Inc()
 		} else {
@@ -920,16 +943,17 @@ func (c *RegionCache) loadRegionByID(bo *Backoffer, regionID uint64) (*Region, e
 			backoffErr = errors.Errorf("loadRegion from PD failed, regionID: %v, err: %v", regionID, err)
 			continue
 		}
-		if meta == nil {
+		if reg == nil || reg.Meta == nil {
 			return nil, errors.Errorf("region not found for regionID %d", regionID)
 		}
-		if len(meta.Peers) == 0 {
-			return nil, errors.New("receive Region with no peer")
+		filterUnavailablePeers(reg)
+		if len(reg.Meta.Peers) == 0 {
+			return nil, errors.New("receive Region with no available peer")
 		}
-		region := &Region{meta: meta}
+		region := &Region{meta: reg.Meta}
 		region.init(c)
-		if leader != nil {
-			c.switchToPeer(region, leader.GetStoreId())
+		if reg.Leader != nil {
+			c.switchToPeer(region, reg.Leader.GetStoreId())
 		}
 		return region, nil
 	}

store/tikv/store_test.go

@@ -139,32 +139,32 @@ func (c *mockPDClient) GetTSAsync(ctx context.Context) pd.TSFuture {
 	return nil
 }
 
-func (c *mockPDClient) GetRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *mockPDClient) GetRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	c.RLock()
 	defer c.RUnlock()
 
 	if c.stop {
-		return nil, nil, errors.Trace(errStopped)
+		return nil, errors.Trace(errStopped)
 	}
 	return c.client.GetRegion(ctx, key)
 }
 
-func (c *mockPDClient) GetPrevRegion(ctx context.Context, key []byte) (*metapb.Region, *metapb.Peer, error) {
+func (c *mockPDClient) GetPrevRegion(ctx context.Context, key []byte) (*pd.Region, error) {
 	c.RLock()
 	defer c.RUnlock()
 
 	if c.stop {
-		return nil, nil, errors.Trace(errStopped)
+		return nil, errors.Trace(errStopped)
 	}
 	return c.client.GetPrevRegion(ctx, key)
 }
 
-func (c *mockPDClient) GetRegionByID(ctx context.Context, regionID uint64) (*metapb.Region, *metapb.Peer, error) {
+func (c *mockPDClient) GetRegionByID(ctx context.Context, regionID uint64) (*pd.Region, error) {
 	c.RLock()
 	defer c.RUnlock()
 
 	if c.stop {
-		return nil, nil, errors.Trace(errStopped)
+		return nil, errors.Trace(errStopped)
 	}
 	return c.client.GetRegionByID(ctx, regionID)
 }