diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 0ea81f19a..dab1a0a96 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -715,7 +715,6 @@ block Blockchain::pop_block_from_blockchain()
   m_blocks_longhash_table.clear();
   m_scan_table.clear();
   m_blocks_txs_check.clear();
-  m_check_txin_table.clear();
 
   CHECK_AND_ASSERT_THROW_MES(update_next_cumulative_weight_limit(), "Error updating next cumulative weight limit");
   uint64_t top_block_height;
@@ -2612,7 +2611,7 @@ void Blockchain::on_new_tx_from_block(const cryptonote::transaction &tx)
 // This function overloads its sister function with
 // an extra value (hash of highest block that holds an output used as input)
 // as a return-by-reference.
-bool Blockchain::check_tx_inputs(transaction& tx, uint64_t& max_used_block_height, crypto::hash& max_used_block_id, tx_verification_context &tvc, bool kept_by_block)
+bool Blockchain::check_tx_inputs(transaction& tx, uint64_t& max_used_block_height, crypto::hash& max_used_block_id, tx_verification_context &tvc, bool kept_by_block) const
 {
   LOG_PRINT_L3("Blockchain::" << __func__);
   CRITICAL_REGION_LOCAL(m_blockchain_lock);
@@ -2643,7 +2642,7 @@ bool Blockchain::check_tx_inputs(transaction& tx, uint64_t& max_used_block_heigh
   return true;
 }
 //------------------------------------------------------------------
-bool Blockchain::check_tx_outputs(const transaction& tx, tx_verification_context &tvc)
+bool Blockchain::check_tx_outputs(const transaction& tx, tx_verification_context &tvc) const
 {
   LOG_PRINT_L3("Blockchain::" << __func__);
   CRITICAL_REGION_LOCAL(m_blockchain_lock);
@@ -2752,7 +2751,7 @@ bool Blockchain::have_tx_keyimges_as_spent(const transaction &tx) const
   }
   return false;
 }
-bool Blockchain::expand_transaction_2(transaction &tx, const crypto::hash &tx_prefix_hash, const std::vector<std::vector<rct::ctkey>> &pubkeys)
+bool Blockchain::expand_transaction_2(transaction &tx, const crypto::hash &tx_prefix_hash, const std::vector<std::vector<rct::ctkey>> &pubkeys) const
 {
   PERF_TIMER(expand_transaction_2);
   CHECK_AND_ASSERT_MES(tx.version == 2, false, "Transaction version is not 2");
@@ -2828,7 +2827,7 @@ bool Blockchain::expand_transaction_2(transaction &tx, const crypto::hash &tx_pr
 //        check_tx_input() rather than here, and use this function simply
 //        to iterate the inputs as necessary (splitting the task
 //        using threads, etc.)
-bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc, uint64_t* pmax_used_block_height)
+bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc, uint64_t* pmax_used_block_height) const
 {
   PERF_TIMER(check_tx_inputs);
   LOG_PRINT_L3("Blockchain::" << __func__);
@@ -2947,13 +2946,6 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
       }
     }
   }
-  auto it = m_check_txin_table.find(tx_prefix_hash);
-  if(it == m_check_txin_table.end())
-  {
-    m_check_txin_table.emplace(tx_prefix_hash, std::unordered_map<crypto::key_image, bool>());
-    it = m_check_txin_table.find(tx_prefix_hash);
-    assert(it != m_check_txin_table.end());
-  }
 
   std::vector<std::vector<rct::ctkey>> pubkeys(tx.vin.size());
   std::vector < uint64_t > results;
@@ -2985,29 +2977,12 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
     {
       // basically, make sure number of inputs == number of signatures
       CHECK_AND_ASSERT_MES(sig_index < tx.signatures.size(), false, "wrong transaction: not signature entry for input with index= " << sig_index);
-
-#if defined(CACHE_VIN_RESULTS)
-      auto itk = it->second.find(in_to_key.k_image);
-      if(itk != it->second.end())
-      {
-        if(!itk->second)
-        {
-          MERROR_VER("Failed ring signature for tx " << get_transaction_hash(tx) << "  vin key with k_image: " << in_to_key.k_image << "  sig_index: " << sig_index);
-          return false;
-        }
-
-        // txin has been verified already, skip
-        sig_index++;
-        continue;
-      }
-#endif
     }
 
     // make sure that output being spent matches up correctly with the
     // signature spending it.
     if (!check_tx_input(tx.version, in_to_key, tx_prefix_hash, tx.version == 1 ? tx.signatures[sig_index] : std::vector<crypto::signature>(), tx.rct_signatures, pubkeys[sig_index], pmax_used_block_height))
     {
-      it->second[in_to_key.k_image] = false;
       MERROR_VER("Failed to check ring signature for tx " << get_transaction_hash(tx) << "  vin key with k_image: " << in_to_key.k_image << "  sig_index: " << sig_index);
       if (pmax_used_block_height) // a default value of NULL is used when called from Blockchain::handle_block_to_main_chain()
       {
@@ -3030,7 +3005,6 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
         check_ring_signature(tx_prefix_hash, in_to_key.k_image, pubkeys[sig_index], tx.signatures[sig_index], results[sig_index]);
         if (!results[sig_index])
         {
-          it->second[in_to_key.k_image] = false;
           MERROR_VER("Failed to check ring signature for tx " << get_transaction_hash(tx) << "  vin key with k_image: " << in_to_key.k_image << "  sig_index: " << sig_index);
 
           if (pmax_used_block_height)  // a default value of NULL is used when called from Blockchain::handle_block_to_main_chain()
@@ -3040,7 +3014,6 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
 
           return false;
         }
-        it->second[in_to_key.k_image] = true;
       }
     }
 
@@ -3058,7 +3031,6 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
       for (size_t i = 0; i < tx.vin.size(); i++)
       {
         const txin_to_key& in_to_key = boost::get<txin_to_key>(tx.vin[i]);
-        it->second[in_to_key.k_image] = results[i];
         if(!failed && !results[i])
           failed = true;
       }
@@ -3232,7 +3204,7 @@ bool Blockchain::check_tx_inputs(transaction& tx, tx_verification_context &tvc,
 }
 
 //------------------------------------------------------------------
-void Blockchain::check_ring_signature(const crypto::hash &tx_prefix_hash, const crypto::key_image &key_image, const std::vector<rct::ctkey> &pubkeys, const std::vector<crypto::signature>& sig, uint64_t &result)
+void Blockchain::check_ring_signature(const crypto::hash &tx_prefix_hash, const crypto::key_image &key_image, const std::vector<rct::ctkey> &pubkeys, const std::vector<crypto::signature>& sig, uint64_t &result) const
 {
   std::vector<const crypto::public_key *> p_output_keys;
   p_output_keys.reserve(pubkeys.size());
@@ -3418,7 +3390,7 @@ bool Blockchain::is_tx_spendtime_unlocked(uint64_t unlock_time) const
 // This function locates all outputs associated with a given input (mixins)
 // and validates that they exist and are usable.  It also checks the ring
 // signature for each input.
-bool Blockchain::check_tx_input(size_t tx_version, const txin_to_key& txin, const crypto::hash& tx_prefix_hash, const std::vector<crypto::signature>& sig, const rct::rctSig &rct_signatures, std::vector<rct::ctkey> &output_keys, uint64_t* pmax_related_block_height)
+bool Blockchain::check_tx_input(size_t tx_version, const txin_to_key& txin, const crypto::hash& tx_prefix_hash, const std::vector<crypto::signature>& sig, const rct::rctSig &rct_signatures, std::vector<rct::ctkey> &output_keys, uint64_t* pmax_related_block_height) const
 {
   LOG_PRINT_L3("Blockchain::" << __func__);
 
@@ -4255,7 +4227,6 @@ bool Blockchain::cleanup_handle_incoming_blocks(bool force_sync)
   m_blocks_longhash_table.clear();
   m_scan_table.clear();
   m_blocks_txs_check.clear();
-  m_check_txin_table.clear();
 
   // when we're well clear of the precomputed hashes, free the memory
   if (!m_blocks_hash_check.empty() && m_db->height() > m_blocks_hash_check.size() + 4096)
@@ -4544,7 +4515,6 @@ bool Blockchain::prepare_handle_incoming_blocks(const std::vector<block_complete
   m_fake_pow_calc_time = 0;
 
   m_scan_table.clear();
-  m_check_txin_table.clear();
 
   TIME_MEASURE_FINISH(prepare);
   m_fake_pow_calc_time = prepare / blocks_entry.size();
diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h
index d95f2dceb..f58059a6d 100644
--- a/src/cryptonote_core/blockchain.h
+++ b/src/cryptonote_core/blockchain.h
@@ -548,7 +548,7 @@ namespace cryptonote
      *
      * @return false if any input is invalid, otherwise true
      */
-    bool check_tx_inputs(transaction& tx, uint64_t& pmax_used_block_height, crypto::hash& max_used_block_id, tx_verification_context &tvc, bool kept_by_block = false);
+    bool check_tx_inputs(transaction& tx, uint64_t& pmax_used_block_height, crypto::hash& max_used_block_id, tx_verification_context &tvc, bool kept_by_block = false) const;
 
     /**
      * @brief get fee quantization mask
@@ -615,7 +615,7 @@ namespace cryptonote
      *
      * @return false if any outputs do not conform, otherwise true
      */
-    bool check_tx_outputs(const transaction& tx, tx_verification_context &tvc);
+    bool check_tx_outputs(const transaction& tx, tx_verification_context &tvc) const;
 
     /**
      * @brief gets the block weight limit based on recent blocks
@@ -1020,7 +1020,6 @@ namespace cryptonote
     // metadata containers
     std::unordered_map<crypto::hash, std::unordered_map<crypto::key_image, std::vector<output_data_t>>> m_scan_table;
     std::unordered_map<crypto::hash, crypto::hash> m_blocks_longhash_table;
-    std::unordered_map<crypto::hash, std::unordered_map<crypto::key_image, bool>> m_check_txin_table;
 
     // SHA-3 hashes for each block and for fast pow checking
     std::vector<crypto::hash> m_blocks_hash_of_hashes;
@@ -1127,7 +1126,7 @@ namespace cryptonote
      *
      * @return false if any output is not yet unlocked, or is missing, otherwise true
      */
-    bool check_tx_input(size_t tx_version,const txin_to_key& txin, const crypto::hash& tx_prefix_hash, const std::vector<crypto::signature>& sig, const rct::rctSig &rct_signatures, std::vector<rct::ctkey> &output_keys, uint64_t* pmax_related_block_height);
+    bool check_tx_input(size_t tx_version,const txin_to_key& txin, const crypto::hash& tx_prefix_hash, const std::vector<crypto::signature>& sig, const rct::rctSig &rct_signatures, std::vector<rct::ctkey> &output_keys, uint64_t* pmax_related_block_height) const;
 
     /**
      * @brief validate a transaction's inputs and their keys
@@ -1149,7 +1148,7 @@ namespace cryptonote
      *
      * @return false if any validation step fails, otherwise true
      */
-    bool check_tx_inputs(transaction& tx, tx_verification_context &tvc, uint64_t* pmax_used_block_height = NULL);
+    bool check_tx_inputs(transaction& tx, tx_verification_context &tvc, uint64_t* pmax_used_block_height = NULL) const;
 
     /**
      * @brief performs a blockchain reorganization according to the longest chain rule
@@ -1429,7 +1428,7 @@ namespace cryptonote
      * @param result false if the ring signature is invalid, otherwise true
      */
     void check_ring_signature(const crypto::hash &tx_prefix_hash, const crypto::key_image &key_image,
-        const std::vector<rct::ctkey> &pubkeys, const std::vector<crypto::signature> &sig, uint64_t &result);
+        const std::vector<rct::ctkey> &pubkeys, const std::vector<crypto::signature> &sig, uint64_t &result) const;
 
     /**
      * @brief loads block hashes from compiled-in data set
@@ -1449,7 +1448,7 @@ namespace cryptonote
      * can be reconstituted by the receiver. This function expands
      * that implicit data.
      */
-    bool expand_transaction_2(transaction &tx, const crypto::hash &tx_prefix_hash, const std::vector<std::vector<rct::ctkey>> &pubkeys);
+    bool expand_transaction_2(transaction &tx, const crypto::hash &tx_prefix_hash, const std::vector<std::vector<rct::ctkey>> &pubkeys) const;
 
     /**
      * @brief invalidates any cached block template