Merge pull request #4934

5dc590cb wallet2: speedup output tracking (moneromooo-monero)
db3f2a91 wallet: optionally keep track of owned outputs uses (moneromooo-monero)

4 files changed, 156 insertions, 30 deletions

diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index 75cd31f19..bdb6d2bfe 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -146,7 +146,7 @@ namespace
   const char* USAGE_START_MINING("start_mining [<number_of_threads>] [bg_mining] [ignore_battery]");
   const char* USAGE_SET_DAEMON("set_daemon <host>[:<port>] [trusted|untrusted]");
   const char* USAGE_SHOW_BALANCE("balance [detail]");
-  const char* USAGE_INCOMING_TRANSFERS("incoming_transfers [available|unavailable] [verbose] [index=<N1>[,<N2>[,...]]]");
+  const char* USAGE_INCOMING_TRANSFERS("incoming_transfers [available|unavailable] [verbose] [uses] [index=<N1>[,<N2>[,...]]]");
   const char* USAGE_PAYMENTS("payments <PID_1> [<PID_2> ... <PID_N>]");
   const char* USAGE_PAYMENT_ID("payment_id");
   const char* USAGE_TRANSFER("transfer [index=<N1>[,<N2>,...]] [<priority>] [<ring_size>] (<URI> | <address> <amount>) [<payment_id>]");
@@ -2488,6 +2488,19 @@ bool simple_wallet::set_ignore_fractional_outputs(const std::vector<std::string>
   return true;
 }
 
+bool simple_wallet::set_track_uses(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
+{
+  const auto pwd_container = get_and_verify_password();
+  if (pwd_container)
+  {
+    parse_bool_and_use(args[1], [&](bool r) {
+      m_wallet->track_uses(r);
+      m_wallet->rewrite(m_wallet_file, pwd_container->password());
+    });
+  }
+  return true;
+}
+
 bool simple_wallet::set_device_name(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
 {
   const auto pwd_container = get_and_verify_password();
@@ -3032,6 +3045,7 @@ bool simple_wallet::set_variable(const std::vector<std::string> &args)
     success_msg_writer() << "subaddress-lookahead = " << lookahead.first << ":" << lookahead.second;
     success_msg_writer() << "segregation-height = " << m_wallet->segregation_height();
     success_msg_writer() << "ignore-fractional-outputs = " << m_wallet->ignore_fractional_outputs();
+    success_msg_writer() << "track-uses = " << m_wallet->track_uses();
     success_msg_writer() << "device_name = " << m_wallet->device_name();
     return true;
   }
@@ -3088,6 +3102,7 @@ bool simple_wallet::set_variable(const std::vector<std::string> &args)
     CHECK_SIMPLE_VARIABLE("subaddress-lookahead", set_subaddress_lookahead, tr("<major>:<minor>"));
     CHECK_SIMPLE_VARIABLE("segregation-height", set_segregation_height, tr("unsigned integer"));
     CHECK_SIMPLE_VARIABLE("ignore-fractional-outputs", set_ignore_fractional_outputs, tr("0 or 1"));
+    CHECK_SIMPLE_VARIABLE("track-uses", set_track_uses, tr("0 or 1"));
     CHECK_SIMPLE_VARIABLE("device-name", set_device_name, tr("<device_name[:device_spec]>"));
   }
   fail_msg_writer() << tr("set: unrecognized argument(s)");
@@ -4813,6 +4828,7 @@ bool simple_wallet::show_incoming_transfers(const std::vector<std::string>& args
   bool filter = false;
   bool available = false;
   bool verbose = false;
+  bool uses = false;
   if (local_args.size() > 0)
   {
     if (local_args[0] == "available")
@@ -4828,12 +4844,22 @@ bool simple_wallet::show_incoming_transfers(const std::vector<std::string>& args
       local_args.erase(local_args.begin());
     }
   }
-  if (local_args.size() > 0 && local_args[0] == "verbose")
+  while (local_args.size() > 0)
   {
-    verbose = true;
+    if (local_args[0] == "verbose")
+      verbose = true;
+    else if (local_args[0] == "uses")
+      uses = true;
+    else
+    {
+      fail_msg_writer() << tr("Invalid keyword: ") << local_args.front();
+      break;
+    }
     local_args.erase(local_args.begin());
   }
 
+  const uint64_t blockchain_height = m_wallet->get_blockchain_current_height();
+
   PAUSE_READLINE();
 
   std::set<uint32_t> subaddr_indices;
@@ -4867,9 +4893,16 @@ bool simple_wallet::show_incoming_transfers(const std::vector<std::string>& args
           verbose_string = (boost::format("%68s%68s") % tr("pubkey") % tr("key image")).str();
         message_writer() << boost::format("%21s%8s%12s%8s%16s%68s%16s%s") % tr("amount") % tr("spent") % tr("unlocked") % tr("ringct") % tr("global index") % tr("tx id") % tr("addr index") % verbose_string;
       }
-      std::string verbose_string;
+      std::string extra_string;
       if (verbose)
-        verbose_string = (boost::format("%68s%68s") % td.get_public_key() % (td.m_key_image_known ? epee::string_tools::pod_to_hex(td.m_key_image) : td.m_key_image_partial ? (epee::string_tools::pod_to_hex(td.m_key_image) + "/p") : std::string(64, '?'))).str();
+        extra_string += (boost::format("%68s%68s") % td.get_public_key() % (td.m_key_image_known ? epee::string_tools::pod_to_hex(td.m_key_image) : td.m_key_image_partial ? (epee::string_tools::pod_to_hex(td.m_key_image) + "/p") : std::string(64, '?'))).str();
+      if (uses)
+      {
+        std::vector<uint64_t> heights;
+        for (const auto &e: td.m_uses) heights.push_back(e.first);
+        const std::pair<std::string, std::string> line = show_outputs_line(heights, blockchain_height, td.m_spent_height);
+        extra_string += tr("Heights: ") + line.first + "\n" + line.second;
+      }
       message_writer(td.m_spent ? console_color_magenta : console_color_green, false) <<
         boost::format("%21s%8s%12s%8s%16u%68s%16u%s") %
         print_money(td.amount()) %
@@ -4879,7 +4912,7 @@ bool simple_wallet::show_incoming_transfers(const std::vector<std::string>& args
         td.m_global_output_index %
         td.m_txid %
         td.m_subaddr_index.minor %
-        verbose_string;
+        extra_string;
       ++transfers_found;
     }
   }
@@ -5031,6 +5064,33 @@ bool simple_wallet::rescan_spent(const std::vector<std::string> &args)
   return true;
 }
 //----------------------------------------------------------------------------------------------------
+std::pair<std::string, std::string> simple_wallet::show_outputs_line(const std::vector<uint64_t> &heights, uint64_t blockchain_height, uint64_t highlight_height) const
+{
+  std::stringstream ostr;
+
+  for (uint64_t h: heights)
+    blockchain_height = std::max(blockchain_height, h);
+
+  for (size_t j = 0; j < heights.size(); ++j)
+    ostr << (heights[j] == highlight_height ? " *" : " ") << heights[j];
+
+  // visualize the distribution, using the code by moneroexamples onion-monero-viewer
+  const uint64_t resolution = 79;
+  std::string ring_str(resolution, '_');
+  for (size_t j = 0; j < heights.size(); ++j)
+  {
+    uint64_t pos = (heights[j] * resolution) / blockchain_height;
+    ring_str[pos] = 'o';
+  }
+  if (highlight_height < blockchain_height)
+  {
+    uint64_t pos = (highlight_height * resolution) / blockchain_height;
+    ring_str[pos] = '*';
+  }
+
+  return std::make_pair(ostr.str(), ring_str);
+}
+//----------------------------------------------------------------------------------------------------
 bool simple_wallet::print_ring_members(const std::vector<tools::wallet2::pending_tx>& ptx_vector, std::ostream& ostr)
 {
   uint32_t version;
@@ -5101,21 +5161,18 @@ bool simple_wallet::print_ring_members(const std::vector<tools::wallet2::pending
         }
       }
       ostr << tr("\nOriginating block heights: ");
-      for (size_t j = 0; j < absolute_offsets.size(); ++j)
-        ostr << tr(j == source.real_output ? " *" : " ") << res.outs[j].height;
       spent_key_height[i] = res.outs[source.real_output].height;
       spent_key_txid  [i] = res.outs[source.real_output].txid;
-      // visualize the distribution, using the code by moneroexamples onion-monero-viewer
-      const uint64_t resolution = 79;
-      std::string ring_str(resolution, '_');
+      std::vector<uint64_t> heights(absolute_offsets.size(), 0);
+      uint64_t highlight_height = std::numeric_limits<uint64_t>::max();
       for (size_t j = 0; j < absolute_offsets.size(); ++j)
       {
-        uint64_t pos = (res.outs[j].height * resolution) / blockchain_height;
-        ring_str[pos] = 'o';
+        heights[j] = res.outs[j].height;
+        if (j == source.real_output)
+          highlight_height = heights[j];
       }
-      uint64_t pos = (res.outs[source.real_output].height * resolution) / blockchain_height;
-      ring_str[pos] = '*';
-      ostr << tr("\n|") << ring_str << tr("|\n");
+      std::pair<std::string, std::string> ring_str = show_outputs_line(heights, highlight_height);
+      ostr << ring_str.first << tr("\n|") << ring_str.second << tr("|\n");
     }
     // warn if rings contain keys originating from the same tx or temporally very close block heights
     bool are_keys_from_same_tx      = false;
diff --git a/src/simplewallet/simplewallet.h b/src/simplewallet/simplewallet.h
index 5010e3adc..e49da8c18 100644
--- a/src/simplewallet/simplewallet.h
+++ b/src/simplewallet/simplewallet.h
@@ -142,6 +142,7 @@ namespace cryptonote
     bool set_subaddress_lookahead(const std::vector<std::string> &args = std::vector<std::string>());
     bool set_segregation_height(const std::vector<std::string> &args = std::vector<std::string>());
     bool set_ignore_fractional_outputs(const std::vector<std::string> &args = std::vector<std::string>());
+    bool set_track_uses(const std::vector<std::string> &args = std::vector<std::string>());
     bool set_device_name(const std::vector<std::string> &args = std::vector<std::string>());
     bool help(const std::vector<std::string> &args = std::vector<std::string>());
     bool start_mining(const std::vector<std::string> &args);
@@ -251,6 +252,7 @@ namespace cryptonote
     bool print_seed(bool encrypted);
     void key_images_sync_intern();
     void on_refresh_finished(uint64_t start_height, uint64_t fetched_blocks, bool is_init, bool received_money);
+    std::pair<std::string, std::string> show_outputs_line(const std::vector<uint64_t> &heights, uint64_t blockchain_height, uint64_t highlight_height = std::numeric_limits<uint64_t>::max()) const;
 
     struct transfer_view
     {
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 0d2faca54..98f0a7f68 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -894,6 +894,7 @@ wallet2::wallet2(network_type nettype, uint64_t kdf_rounds, bool unattended):
   m_key_reuse_mitigation2(true),
   m_segregation_height(0),
   m_ignore_fractional_outputs(true),
+  m_track_uses(false),
   m_is_initialized(false),
   m_kdf_rounds(kdf_rounds),
   is_old_file_format(false),
@@ -1446,8 +1447,9 @@ void wallet2::cache_tx_data(const cryptonote::transaction& tx, const crypto::has
   }
 }
 //----------------------------------------------------------------------------------------------------
-void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen, const tx_cache_data &tx_cache_data)
+void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen, const tx_cache_data &tx_cache_data, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache)
 {
+  PERF_TIMER(process_new_transaction);
   // In this function, tx (probably) only contains the base information
   // (that is, the prunable stuff may or may not be included)
   if (!miner_tx && !pool)
@@ -1684,6 +1686,8 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
             if (!m_multisig && !m_watch_only)
 	      m_key_images[td.m_key_image] = m_transfers.size()-1;
 	    m_pub_keys[tx_scan_info[o].in_ephemeral.pub] = m_transfers.size()-1;
+            if (output_tracker_cache)
+              (*output_tracker_cache)[std::make_pair(tx.vout[o].amount, td.m_global_output_index)] = m_transfers.size() - 1;
             if (m_multisig)
             {
               THROW_WALLET_EXCEPTION_IF(!m_multisig_rescan_k && m_multisig_rescan_info,
@@ -1749,6 +1753,8 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
               td.m_mask = rct::identity();
               td.m_rct = false;
             }
+            if (output_tracker_cache)
+              (*output_tracker_cache)[std::make_pair(tx.vout[o].amount, td.m_global_output_index)] = kit->second;
             if (m_multisig)
             {
               THROW_WALLET_EXCEPTION_IF(!m_multisig_rescan_k && m_multisig_rescan_info,
@@ -1780,11 +1786,12 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
   {
     if(in.type() != typeid(cryptonote::txin_to_key))
       continue;
-    auto it = m_key_images.find(boost::get<cryptonote::txin_to_key>(in).k_image);
+    const cryptonote::txin_to_key &in_to_key = boost::get<cryptonote::txin_to_key>(in);
+    auto it = m_key_images.find(in_to_key.k_image);
     if(it != m_key_images.end())
     {
       transfer_details& td = m_transfers[it->second];
-      uint64_t amount = boost::get<cryptonote::txin_to_key>(in).amount;
+      uint64_t amount = in_to_key.amount;
       if (amount > 0)
       {
         if(amount != td.amount())
@@ -1815,6 +1822,34 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
           m_callback->on_money_spent(height, txid, tx, amount, tx, td.m_subaddr_index);
       }
     }
+
+    if (!pool && m_track_uses)
+    {
+      PERF_TIMER(track_uses);
+      const uint64_t amount = in_to_key.amount;
+      std::vector<uint64_t> offsets = cryptonote::relative_output_offsets_to_absolute(in_to_key.key_offsets);
+      if (output_tracker_cache)
+      {
+        for (uint64_t offset: offsets)
+        {
+          const std::map<std::pair<uint64_t, uint64_t>, size_t>::const_iterator i = output_tracker_cache->find(std::make_pair(amount, offset));
+          if (i != output_tracker_cache->end())
+          {
+            size_t idx = i->second;
+            THROW_WALLET_EXCEPTION_IF(idx >= m_transfers.size(), error::wallet_internal_error, "Output tracker cache index out of range");
+            m_transfers[idx].m_uses.push_back(std::make_pair(height, txid));
+          }
+        }
+      }
+      else for (transfer_details &td: m_transfers)
+      {
+        if (amount != in_to_key.amount)
+          continue;
+        for (uint64_t offset: offsets)
+          if (offset == td.m_global_output_index)
+            td.m_uses.push_back(std::make_pair(height, txid));
+      }
+    }
   }
 
   uint64_t fee = miner_tx ? 0 : tx.version == 1 ? tx_money_spent_in_ins - get_outs_money_amount(tx) : tx.rct_signatures.txnFee;
@@ -1997,7 +2032,7 @@ void wallet2::process_outgoing(const crypto::hash &txid, const cryptonote::trans
   add_rings(tx);
 }
 //----------------------------------------------------------------------------------------------------
-void wallet2::process_new_blockchain_entry(const cryptonote::block& b, const cryptonote::block_complete_entry& bche, const parsed_block &parsed_block, const crypto::hash& bl_id, uint64_t height, const std::vector<tx_cache_data> &tx_cache_data, size_t tx_cache_data_offset)
+void wallet2::process_new_blockchain_entry(const cryptonote::block& b, const cryptonote::block_complete_entry& bche, const parsed_block &parsed_block, const crypto::hash& bl_id, uint64_t height, const std::vector<tx_cache_data> &tx_cache_data, size_t tx_cache_data_offset, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache)
 {
   THROW_WALLET_EXCEPTION_IF(bche.txs.size() + 1 != parsed_block.o_indices.indices.size(), error::wallet_internal_error,
       "block transactions=" + std::to_string(bche.txs.size()) +
@@ -2010,7 +2045,7 @@ void wallet2::process_new_blockchain_entry(const cryptonote::block& b, const cry
   {
     TIME_MEASURE_START(miner_tx_handle_time);
     if (m_refresh_type != RefreshNoCoinbase)
-      process_new_transaction(get_transaction_hash(b.miner_tx), b.miner_tx, parsed_block.o_indices.indices[0].indices, height, b.timestamp, true, false, false, tx_cache_data[tx_cache_data_offset]);
+      process_new_transaction(get_transaction_hash(b.miner_tx), b.miner_tx, parsed_block.o_indices.indices[0].indices, height, b.timestamp, true, false, false, tx_cache_data[tx_cache_data_offset], output_tracker_cache);
     ++tx_cache_data_offset;
     TIME_MEASURE_FINISH(miner_tx_handle_time);
 
@@ -2019,7 +2054,7 @@ void wallet2::process_new_blockchain_entry(const cryptonote::block& b, const cry
     THROW_WALLET_EXCEPTION_IF(bche.txs.size() != parsed_block.txes.size(), error::wallet_internal_error, "Wrong amount of transactions for block");
     for (size_t idx = 0; idx < b.tx_hashes.size(); ++idx)
     {
-      process_new_transaction(b.tx_hashes[idx], parsed_block.txes[idx], parsed_block.o_indices.indices[idx+1].indices, height, b.timestamp, false, false, false, tx_cache_data[tx_cache_data_offset++]);
+      process_new_transaction(b.tx_hashes[idx], parsed_block.txes[idx], parsed_block.o_indices.indices[idx+1].indices, height, b.timestamp, false, false, false, tx_cache_data[tx_cache_data_offset++], output_tracker_cache);
     }
     TIME_MEASURE_FINISH(txs_handle_time);
     m_last_block_reward = cryptonote::get_outs_money_amount(b.miner_tx);
@@ -2117,7 +2152,7 @@ void wallet2::pull_hashes(uint64_t start_height, uint64_t &blocks_start_height,
   hashes = std::move(res.m_block_ids);
 }
 //----------------------------------------------------------------------------------------------------
-void wallet2::process_parsed_blocks(uint64_t start_height, const std::vector<cryptonote::block_complete_entry> &blocks, const std::vector<parsed_block> &parsed_blocks, uint64_t& blocks_added)
+void wallet2::process_parsed_blocks(uint64_t start_height, const std::vector<cryptonote::block_complete_entry> &blocks, const std::vector<parsed_block> &parsed_blocks, uint64_t& blocks_added, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache)
 {
   size_t current_index = start_height;
   blocks_added = 0;
@@ -2224,7 +2259,7 @@ void wallet2::process_parsed_blocks(uint64_t start_height, const std::vector<cry
 
     if(current_index >= m_blockchain.size())
     {
-      process_new_blockchain_entry(bl, blocks[i], parsed_blocks[i], bl_id, current_index, tx_cache_data, tx_cache_data_offset);
+      process_new_blockchain_entry(bl, blocks[i], parsed_blocks[i], bl_id, current_index, tx_cache_data, tx_cache_data_offset, output_tracker_cache);
       ++blocks_added;
     }
     else if(bl_id != m_blockchain[current_index])
@@ -2236,7 +2271,7 @@ void wallet2::process_parsed_blocks(uint64_t start_height, const std::vector<cry
         string_tools::pod_to_hex(m_blockchain[current_index]));
 
       detach_blockchain(current_index);
-      process_new_blockchain_entry(bl, blocks[i], parsed_blocks[i], bl_id, current_index, tx_cache_data, tx_cache_data_offset);
+      process_new_blockchain_entry(bl, blocks[i], parsed_blocks[i], bl_id, current_index, tx_cache_data, tx_cache_data_offset, output_tracker_cache);
     }
     else
     {
@@ -2669,6 +2704,17 @@ bool wallet2::delete_address_book_row(std::size_t row_id) {
 }
 
 //----------------------------------------------------------------------------------------------------
+std::shared_ptr<std::map<std::pair<uint64_t, uint64_t>, size_t>> wallet2::create_output_tracker_cache() const
+{
+  std::shared_ptr<std::map<std::pair<uint64_t, uint64_t>, size_t>> cache{new std::map<std::pair<uint64_t, uint64_t>, size_t>()};
+  for (size_t i = 0; i < m_transfers.size(); ++i)
+  {
+    const transfer_details &td = m_transfers[i];
+    (*cache)[std::make_pair(td.is_rct() ? 0 : td.amount(), td.m_global_output_index)] = i;
+  }
+  return cache;
+}
+//----------------------------------------------------------------------------------------------------
 void wallet2::refresh(bool trusted_daemon, uint64_t start_height, uint64_t & blocks_fetched, bool& received_money)
 {
   if(m_light_wallet) {
@@ -2715,6 +2761,7 @@ void wallet2::refresh(bool trusted_daemon, uint64_t start_height, uint64_t & blo
   std::vector<cryptonote::block_complete_entry> blocks;
   std::vector<parsed_block> parsed_blocks;
   bool refreshed = false;
+  std::shared_ptr<std::map<std::pair<uint64_t, uint64_t>, size_t>> output_tracker_cache;
 
   // pull the first set of blocks
   get_short_chain_history(short_chain_history, (m_first_refresh_done || trusted_daemon) ? 1 : FIRST_REFRESH_GRANULARITY);
@@ -2768,7 +2815,7 @@ void wallet2::refresh(bool trusted_daemon, uint64_t start_height, uint64_t & blo
       {
         try
         {
-          process_parsed_blocks(blocks_start_height, blocks, parsed_blocks, added_blocks);
+          process_parsed_blocks(blocks_start_height, blocks, parsed_blocks, added_blocks, output_tracker_cache.get());
         }
         catch (const tools::error::out_of_hashchain_bounds_error&)
         {
@@ -2811,6 +2858,11 @@ void wallet2::refresh(bool trusted_daemon, uint64_t start_height, uint64_t & blo
         throw std::runtime_error("proxy exception in refresh thread");
       }
 
+      // if we've got at least 10 blocks to refresh, assume we're starting
+      // a long refresh, and setup a tracking output cache if we need to
+      if (m_track_uses && !output_tracker_cache && next_blocks.size() >= 10)
+        output_tracker_cache = create_output_tracker_cache();
+
       // switch to the new blocks from the daemon
       blocks_start_height = next_blocks_start_height;
       blocks = std::move(next_blocks);
@@ -3183,6 +3235,9 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
   value2.SetInt(m_ignore_fractional_outputs ? 1 : 0);
   json.AddMember("ignore_fractional_outputs", value2, json.GetAllocator());
 
+  value2.SetInt(m_track_uses ? 1 : 0);
+  json.AddMember("track_uses", value2, json.GetAllocator());
+
   value2.SetUint(m_subaddress_lookahead_major);
   json.AddMember("subaddress_lookahead_major", value2, json.GetAllocator());
 
@@ -3329,6 +3384,7 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     m_key_reuse_mitigation2 = true;
     m_segregation_height = 0;
     m_ignore_fractional_outputs = true;
+    m_track_uses = false;
     m_subaddress_lookahead_major = SUBADDRESS_LOOKAHEAD_MAJOR;
     m_subaddress_lookahead_minor = SUBADDRESS_LOOKAHEAD_MINOR;
     m_original_keys_available = false;
@@ -3481,6 +3537,8 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     m_segregation_height = field_segregation_height;
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, ignore_fractional_outputs, int, Int, false, true);
     m_ignore_fractional_outputs = field_ignore_fractional_outputs;
+    GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, track_uses, int, Int, false, false);
+    m_track_uses = field_track_uses;
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, subaddress_lookahead_major, uint32_t, Uint, false, SUBADDRESS_LOOKAHEAD_MAJOR);
     m_subaddress_lookahead_major = field_subaddress_lookahead_major;
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, subaddress_lookahead_minor, uint32_t, Uint, false, SUBADDRESS_LOOKAHEAD_MINOR);
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index ace01a235..5b1988080 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -273,6 +273,7 @@ namespace tools
       bool m_key_image_partial;
       std::vector<rct::key> m_multisig_k;
       std::vector<multisig_info> m_multisig_info; // one per other participant
+      std::vector<std::pair<uint64_t, crypto::hash>> m_uses;
 
       bool is_rct() const { return m_rct; }
       uint64_t amount() const { return m_amount; }
@@ -297,6 +298,7 @@ namespace tools
         FIELD(m_key_image_partial)
         FIELD(m_multisig_k)
         FIELD(m_multisig_info)
+        FIELD(m_uses)
       END_SERIALIZE()
     };
 
@@ -984,6 +986,8 @@ namespace tools
     void ignore_fractional_outputs(bool value) { m_ignore_fractional_outputs = value; }
     bool confirm_non_default_ring_size() const { return m_confirm_non_default_ring_size; }
     void confirm_non_default_ring_size(bool always) { m_confirm_non_default_ring_size = always; }
+    bool track_uses() const { return m_track_uses; }
+    void track_uses(bool value) { m_track_uses = value; }
     const std::string & device_name() const { return m_device_name; }
     void device_name(const std::string & device_name) { m_device_name = device_name; }
     const std::string & device_derivation_path() const { return m_device_derivation_path; }
@@ -1249,8 +1253,8 @@ namespace tools
      * \param password       Password of wallet file
      */
     bool load_keys(const std::string& keys_file_name, const epee::wipeable_string& password);
-    void process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen, const tx_cache_data &tx_cache_data);
-    void process_new_blockchain_entry(const cryptonote::block& b, const cryptonote::block_complete_entry& bche, const parsed_block &parsed_block, const crypto::hash& bl_id, uint64_t height, const std::vector<tx_cache_data> &tx_cache_data, size_t tx_cache_data_offset);
+    void process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen, const tx_cache_data &tx_cache_data, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache = NULL);
+    void process_new_blockchain_entry(const cryptonote::block& b, const cryptonote::block_complete_entry& bche, const parsed_block &parsed_block, const crypto::hash& bl_id, uint64_t height, const std::vector<tx_cache_data> &tx_cache_data, size_t tx_cache_data_offset, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache = NULL);
     void detach_blockchain(uint64_t height);
     void get_short_chain_history(std::list<crypto::hash>& ids, uint64_t granularity = 1) const;
     bool clear();
@@ -1258,7 +1262,7 @@ namespace tools
     void pull_hashes(uint64_t start_height, uint64_t& blocks_start_height, const std::list<crypto::hash> &short_chain_history, std::vector<crypto::hash> &hashes);
     void fast_refresh(uint64_t stop_height, uint64_t &blocks_start_height, std::list<crypto::hash> &short_chain_history, bool force = false);
     void pull_and_parse_next_blocks(uint64_t start_height, uint64_t &blocks_start_height, std::list<crypto::hash> &short_chain_history, const std::vector<cryptonote::block_complete_entry> &prev_blocks, const std::vector<parsed_block> &prev_parsed_blocks, std::vector<cryptonote::block_complete_entry> &blocks, std::vector<parsed_block> &parsed_blocks, bool &error);
-    void process_parsed_blocks(uint64_t start_height, const std::vector<cryptonote::block_complete_entry> &blocks, const std::vector<parsed_block> &parsed_blocks, uint64_t& blocks_added);
+    void process_parsed_blocks(uint64_t start_height, const std::vector<cryptonote::block_complete_entry> &blocks, const std::vector<parsed_block> &parsed_blocks, uint64_t& blocks_added, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache = NULL);
     uint64_t select_transfers(uint64_t needed_money, std::vector<size_t> unused_transfers_indices, std::vector<size_t>& selected_transfers) const;
     bool prepare_file_names(const std::string& file_path);
     void process_unconfirmed(const crypto::hash &txid, const cryptonote::transaction& tx, uint64_t height);
@@ -1312,6 +1316,7 @@ namespace tools
       std::unordered_set<crypto::public_key> &pkeys) const;
 
     void cache_tx_data(const cryptonote::transaction& tx, const crypto::hash &txid, tx_cache_data &tx_cache_data) const;
+    std::shared_ptr<std::map<std::pair<uint64_t, uint64_t>, size_t>> create_output_tracker_cache() const;
 
     void setup_new_blockchain();
     void create_keys_file(const std::string &wallet_, bool watch_only, const epee::wipeable_string &password, bool create_address_file);
@@ -1395,6 +1400,7 @@ namespace tools
     bool m_key_reuse_mitigation2;
     uint64_t m_segregation_height;
     bool m_ignore_fractional_outputs;
+    bool m_track_uses;
     bool m_is_initialized;
     NodeRPCProxy m_node_rpc_proxy;
     std::unordered_set<crypto::hash> m_scanned_pool_txs[2];
@@ -1444,7 +1450,7 @@ namespace tools
   };
 }
 BOOST_CLASS_VERSION(tools::wallet2, 27)
-BOOST_CLASS_VERSION(tools::wallet2::transfer_details, 10)
+BOOST_CLASS_VERSION(tools::wallet2::transfer_details, 11)
 BOOST_CLASS_VERSION(tools::wallet2::multisig_info, 1)
 BOOST_CLASS_VERSION(tools::wallet2::multisig_info::LR, 0)
 BOOST_CLASS_VERSION(tools::wallet2::multisig_tx_set, 1)
@@ -1593,6 +1599,9 @@ namespace boost
         return;
       }
       a & x.m_key_image_requested;
+      if (ver < 11)
+        return;
+      a & x.m_uses;
     }
 
     template <class Archive>