Feature/Improves stability in networks with faulty nodes

irohad/consensus/yac/impl/yac.cpp

@@ -183,14 +183,32 @@ namespace iroha {
 
       // ------|Private interface|------
 
-      void Yac::votingStep(VoteMessage vote) {
+      void Yac::votingStep(VoteMessage vote, uint32_t attempt) {
+        log_->info("votingStep got vote: {}, attempt {}", vote, attempt);
         std::unique_lock<std::mutex> lock(mutex_);
 
         auto committed = vote_storage_.isCommitted(vote.hash.vote_round);
         if (committed) {
           return;
         }
 
+        enum { kRotatePeriod = 10 };
+
+        if (0 != attempt && 0 == (attempt % kRotatePeriod)) {
+          vote_storage_.remove(vote.hash.vote_round);
+        }
+
+        /**
+         * 3 attempts to build and commit block before we think that round is
+         * freezed
+         */
+        if (attempt == kRotatePeriod) {
+          vote.hash.vote_hashes.proposal_hash.clear();
+          vote.hash.vote_hashes.block_hash.clear();
+          vote.hash.block_signature.reset();
+          vote = crypto_->getVote(vote.hash);
+        }
+
         auto &cluster_order = getCurrentOrder();
 
         const auto &current_leader = cluster_order.currentLeader();
@@ -200,7 +218,9 @@ namespace iroha {
         propagateStateDirectly(current_leader, {vote});
         cluster_order.switchToNext();
         lock.unlock();
-        timer_->invokeAfterDelay([this, vote] { this->votingStep(vote); });
+
+        timer_->invokeAfterDelay(
+            [this, vote, attempt] { this->votingStep(vote, attempt + 1); });
       }
 
       void Yac::closeRound() {

irohad/consensus/yac/storage/yac_vote_storage.hpp

@@ -84,11 +84,6 @@ namespace iroha {
         findProposalStorage(const VoteMessage &msg,
                             PeersNumberType peers_in_round);
 
-        /**
-         * Remove proposal storage by round
-         */
-        void remove(const Round &round);
-
        public:
         // --------| public api |--------
 
@@ -119,6 +114,11 @@ namespace iroha {
          */
         bool isCommitted(const Round &round);
 
+        /**
+         * Remove proposal storage by round
+         */
+        void remove(const Round &round);
+
         /**
          * Method provide state of processing for concrete proposal/block
          * @param round, in which that proposal/block is being voted

irohad/consensus/yac/yac.hpp

@@ -77,7 +77,7 @@ namespace iroha {
          * Voting step is strategy of propagating vote
          * until commit/reject message received
          */
-        void votingStep(VoteMessage vote);
+        void votingStep(VoteMessage vote, uint32_t attempt = 0);
 
         /**
          * Erase temporary data of current round