Merge pull request #3105 from ipfs/feat/bitswap/dup-prov-cache

bitswap: don't re-provide blocks we've provided very recently

blockservice/blockservice.go

@@ -43,7 +43,15 @@ func New(bs blockstore.Blockstore, rem exchange.Interface) *BlockService {
 // TODO pass a context into this if the remote.HasBlock is going to remain here.
 func (s *BlockService) AddBlock(b blocks.Block) (key.Key, error) {
 	k := b.Key()
-	err := s.Blockstore.Put(b)
+	has, err := s.Blockstore.Has(k)
+	if err != nil {
+		return k, err
+	}
+	if has {
+		return k, nil
+	}
+
+	err = s.Blockstore.Put(b)
 	if err != nil {
 		return k, err
 	}
@@ -54,13 +62,27 @@ func (s *BlockService) AddBlock(b blocks.Block) (key.Key, error) {
 }
 
 func (s *BlockService) AddBlocks(bs []blocks.Block) ([]key.Key, error) {
-	err := s.Blockstore.PutMany(bs)
+	var toput []blocks.Block
+	for _, b := range bs {
+		has, err := s.Blockstore.Has(b.Key())
+		if err != nil {
+			return nil, err
+		}
+
+		if has {
+			continue
+		}
+
+		toput = append(toput, b)
+	}
+
+	err := s.Blockstore.PutMany(toput)
 	if err != nil {
 		return nil, err
 	}
 
 	var ks []key.Key
-	for _, b := range bs {
+	for _, b := range toput {
 		if err := s.Exchange.HasBlock(b); err != nil {
 			return nil, errors.New("blockservice is closed")
 		}

exchange/bitswap/workers.go

@@ -133,6 +133,7 @@ func (bs *Bitswap) provideCollector(ctx context.Context) {
 				log.Debug("newBlocks channel closed")
 				return
 			}
+
 			if keysOut == nil {
 				nextKey = blk.Key()
 				keysOut = bs.provideKeys