diff --git a/src/blocks/checkpoints.dat b/src/blocks/checkpoints.dat
index 1963646d3..cc7272f3a 100644
Binary files a/src/blocks/checkpoints.dat and b/src/blocks/checkpoints.dat differ
diff --git a/src/checkpoints/checkpoints.cpp b/src/checkpoints/checkpoints.cpp
index cbe0888c6..1ce694813 100644
--- a/src/checkpoints/checkpoints.cpp
+++ b/src/checkpoints/checkpoints.cpp
@@ -224,6 +224,7 @@ namespace cryptonote
     ADD_CHECKPOINT2(332100,  "d32c409058c1eceb9a105190c7a5f480b2d6f49f318b18652b49ae971c710124", "0x7c538441cca36");
     ADD_CHECKPOINT2(334000,  "17d3b15f8e1a73e1c61335ee7979e9e3d211b9055e8a7fb2481e5f49a51b1c22", "0x7ddd5a79d69c4");
     ADD_CHECKPOINT2(348500,  "2d43a157f369e2aa26a329b56456142ecd1361f5808c688d97112a2e3bbd23f4", "0x90889ed877ada");
+    ADD_CHECKPOINT2(489400,  "b14f49eae77398117ea93435676100d8b655a804689f73a5a4d0d5e71160d603", "0x1123c39bb52f7e");
     return true;
   }
 
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index 8b246a706..9d117ec09 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -5541,7 +5541,7 @@ void Blockchain::cancel()
 }
 
 #if defined(PER_BLOCK_CHECKPOINT)
-static const char expected_block_hashes_hash[] = "02777e7737e1a325558f28172d5041ed7b6e7026a0d19f3cd128966cad89299d";
+static const char expected_block_hashes_hash[] = "cdb3d018fc4c2505619423a24b2d694348103df9af9a3f4f0cc203f4e21363bd";
 void Blockchain::load_compiled_in_block_hashes(const GetCheckpointsCallback& get_checkpoints)
 {
   if (get_checkpoints == nullptr || !m_fast_sync)
diff --git a/src/ringct/rctSigs.cpp b/src/ringct/rctSigs.cpp
index 7e0b33fd2..278da484f 100644
--- a/src/ringct/rctSigs.cpp
+++ b/src/ringct/rctSigs.cpp
@@ -79,6 +79,7 @@ namespace
 
         return rct::Bulletproof{rct::keyV(n_outs, I), I, I, I, I, I, I, rct::keyV(nrl, I), rct::keyV(nrl, I), I, I, I};
     }
+
     rct::BulletproofPlus make_dummy_bulletproof_plus(const std::vector<uint64_t> &outamounts, rct::keyV &C, rct::keyV &masks)
     {
         const size_t n_outs = outamounts.size();
@@ -109,6 +110,13 @@ namespace
 
         return rct::BulletproofPlus{rct::keyV(n_outs, I), I, I, I, I, I, I, rct::keyV(nrl, I), rct::keyV(nrl, I)};
     }
+
+    rct::clsag make_dummy_clsag(size_t ring_size)
+    {
+        const rct::key I = rct::identity();
+        const size_t n_scalars = ring_size;
+        return rct::clsag{rct::keyV(n_scalars, I), I, I, I};
+    }
 }
 
 namespace rct {
@@ -1400,7 +1408,10 @@ namespace rct {
         {
             if (is_rct_clsag(rv.type))
             {
-                rv.p.CLSAGs[i] = proveRctCLSAGSimple(full_message, rv.mixRing[i], inSk[i], a[i], pseudoOuts[i], kLRki ? &(*kLRki)[i]: NULL, msout ? &msout->c[i] : NULL, msout ? &msout->mu_p[i] : NULL, index[i], hwdev);
+                if (hwdev.get_mode() == hw::device::TRANSACTION_CREATE_FAKE)
+                    rv.p.CLSAGs[i] = make_dummy_clsag(rv.mixRing[i].size());
+                else
+                    rv.p.CLSAGs[i] = proveRctCLSAGSimple(full_message, rv.mixRing[i], inSk[i], a[i], pseudoOuts[i], kLRki ? &(*kLRki)[i]: NULL, msout ? &msout->c[i] : NULL, msout ? &msout->mu_p[i] : NULL, index[i], hwdev);
             }
             else
             {
diff --git a/src/version.cpp.in b/src/version.cpp.in
index 952b11921..6ae2c4939 100644
--- a/src/version.cpp.in
+++ b/src/version.cpp.in
@@ -1,5 +1,5 @@
 #define DEF_MONERO_VERSION_TAG "@VERSIONTAG@"
-#define DEF_MONERO_VERSION "0.10.1.0"
+#define DEF_MONERO_VERSION "0.10.2.0"
 #define DEF_MONERO_RELEASE_NAME "Junkie Jeff"
 #define DEF_MONERO_VERSION_FULL DEF_MONERO_VERSION "-" DEF_MONERO_VERSION_TAG
 #define DEF_MONERO_VERSION_IS_RELEASE @VERSION_IS_RELEASE@
diff --git a/src/wallet/ringdb.cpp b/src/wallet/ringdb.cpp
index dfeb987ca..6a48d8117 100644
--- a/src/wallet/ringdb.cpp
+++ b/src/wallet/ringdb.cpp
@@ -346,12 +346,15 @@ bool ringdb::remove_rings(const crypto::chacha_key &chacha_key, const cryptonote
   return remove_rings(chacha_key, key_images);
 }
 
-bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, std::vector<uint64_t> &outs)
+bool ringdb::get_rings(const crypto::chacha_key &chacha_key, const std::vector<crypto::key_image> &key_images, std::vector<std::vector<uint64_t>> &all_outs)
 {
   MDB_txn *txn;
   int dbr;
   bool tx_active = false;
 
+  all_outs.clear();
+  all_outs.reserve(key_images.size());
+
   dbr = resize_env(env, filename.c_str(), 0);
   THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set env map size: " + std::string(mdb_strerror(dbr)));
   dbr = mdb_txn_begin(env, NULL, 0, &txn);
@@ -359,6 +362,10 @@ bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_im
   epee::misc_utils::auto_scope_leave_caller txn_dtor = epee::misc_utils::create_scope_leave_handler([&](){if (tx_active) mdb_txn_abort(txn);});
   tx_active = true;
 
+  for (size_t i = 0; i < key_images.size(); ++i)
+  {
+  const crypto::key_image &key_image = key_images[i];
+
   MDB_val key, data;
   std::string key_ciphertext = encrypt(key_image, chacha_key, 0);
   key.mv_data = (void*)key_ciphertext.data();
@@ -369,6 +376,7 @@ bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_im
     return false;
   THROW_WALLET_EXCEPTION_IF(data.mv_size <= 0, tools::error::wallet_internal_error, "Invalid ring data size");
 
+  std::vector<uint64_t> outs;
   bool try_v0 = false;
   std::string data_plaintext = decrypt(std::string((const char*)data.mv_data, data.mv_size), key_image, chacha_key, 1);
   try { outs = decompress_ring(data_plaintext, V1TAG); if (outs.empty()) try_v0 = true; }
@@ -382,6 +390,9 @@ bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_im
   MDEBUG("Relative: " << boost::join(outs | boost::adaptors::transformed([](uint64_t out){return std::to_string(out);}), " "));
   outs = cryptonote::relative_output_offsets_to_absolute(outs);
   MDEBUG("Absolute: " << boost::join(outs | boost::adaptors::transformed([](uint64_t out){return std::to_string(out);}), " "));
+  all_outs.push_back(std::move(outs));
+
+  }
 
   dbr = mdb_txn_commit(txn);
   THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to commit txn getting ring from database: " + std::string(mdb_strerror(dbr)));
@@ -389,20 +400,33 @@ bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_im
   return true;
 }
 
-bool ringdb::set_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, const std::vector<uint64_t> &outs, bool relative)
+bool ringdb::get_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, std::vector<uint64_t> &outs)
+{
+  std::vector<std::vector<uint64_t>> all_outs;
+  if (!get_rings(chacha_key, std::vector<crypto::key_image>(1, key_image), all_outs))
+    return false;
+  outs = std::move(all_outs.front());
+  return true;
+}
+
+bool ringdb::set_rings(const crypto::chacha_key &chacha_key, const std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &rings, bool relative)
 {
   MDB_txn *txn;
   int dbr;
   bool tx_active = false;
 
-  dbr = resize_env(env, filename.c_str(), outs.size() * 64);
+  size_t n_outs = 0;
+  for (const auto &e: rings)
+    n_outs += e.second.size();
+  dbr = resize_env(env, filename.c_str(), n_outs * 64);
   THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to set env map size: " + std::string(mdb_strerror(dbr)));
   dbr = mdb_txn_begin(env, NULL, 0, &txn);
   THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to create LMDB transaction: " + std::string(mdb_strerror(dbr)));
   epee::misc_utils::auto_scope_leave_caller txn_dtor = epee::misc_utils::create_scope_leave_handler([&](){if (tx_active) mdb_txn_abort(txn);});
   tx_active = true;
 
-  store_relative_ring(txn, dbi_rings, key_image, relative ? outs : cryptonote::absolute_output_offsets_to_relative(outs), chacha_key);
+  for (const auto &e: rings)
+    store_relative_ring(txn, dbi_rings, e.first, relative ? e.second : cryptonote::absolute_output_offsets_to_relative(e.second), chacha_key);
 
   dbr = mdb_txn_commit(txn);
   THROW_WALLET_EXCEPTION_IF(dbr, tools::error::wallet_internal_error, "Failed to commit txn setting ring to database: " + std::string(mdb_strerror(dbr)));
@@ -410,6 +434,13 @@ bool ringdb::set_ring(const crypto::chacha_key &chacha_key, const crypto::key_im
   return true;
 }
 
+bool ringdb::set_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, const std::vector<uint64_t> &outs, bool relative)
+{
+  std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> rings;
+  rings.push_back(std::make_pair(key_image, outs));
+  return set_rings(chacha_key, rings, relative);
+}
+
 bool ringdb::blackball_worker(const std::vector<std::pair<uint64_t, uint64_t>> &outputs, int op)
 {
   MDB_txn *txn;
diff --git a/src/wallet/ringdb.h b/src/wallet/ringdb.h
index 9c7e624bc..02a4f8b48 100644
--- a/src/wallet/ringdb.h
+++ b/src/wallet/ringdb.h
@@ -48,7 +48,9 @@ namespace tools
     bool remove_rings(const crypto::chacha_key &chacha_key, const std::vector<crypto::key_image> &key_images);
     bool remove_rings(const crypto::chacha_key &chacha_key, const cryptonote::transaction_prefix &tx);
     bool get_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, std::vector<uint64_t> &outs);
+    bool get_rings(const crypto::chacha_key &chacha_key, const std::vector<crypto::key_image> &key_images, std::vector<std::vector<uint64_t>> &all_outs);
     bool set_ring(const crypto::chacha_key &chacha_key, const crypto::key_image &key_image, const std::vector<uint64_t> &outs, bool relative);
+    bool set_rings(const crypto::chacha_key &chacha_key, const std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &rings, bool relative);
 
     bool blackball(const std::pair<uint64_t, uint64_t> &output);
     bool blackball(const std::vector<std::pair<uint64_t, uint64_t>> &outputs);
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 39de21899..d78a9af67 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -8127,6 +8127,14 @@ bool wallet2::get_ring(const crypto::chacha_key &key, const crypto::key_image &k
   catch (const std::exception &e) { return false; }
 }
 
+bool wallet2::get_rings(const crypto::chacha_key &key, const std::vector<crypto::key_image> &key_images, std::vector<std::vector<uint64_t>> &outs)
+{
+  if (!m_ringdb)
+    return false;
+  try { return m_ringdb->get_rings(key, key_images, outs); }
+  catch (const std::exception &e) { return false; }
+}
+
 bool wallet2::get_rings(const crypto::hash &txid, std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &outs)
 {
   for (auto i: m_confirmed_txs)
@@ -8165,6 +8173,15 @@ bool wallet2::set_ring(const crypto::key_image &key_image, const std::vector<uin
   catch (const std::exception &e) { return false; }
 }
 
+bool wallet2::set_rings(const std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &rings, bool relative)
+{
+  if (!m_ringdb)
+    return false;
+
+  try { return m_ringdb->set_rings(get_ringdb_key(), rings, relative); }
+  catch (const std::exception &e) { return false; }
+}
+
 bool wallet2::unset_ring(const std::vector<crypto::key_image> &key_images)
 {
   if (!m_ringdb)
@@ -8339,7 +8356,7 @@ bool wallet2::is_keys_file_locked() const
   return m_keys_file_locker->locked();
 }
 
-bool wallet2::tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& output_public_key, const rct::key& mask, uint64_t real_index, bool unlocked) const
+bool wallet2::tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& output_public_key, const rct::key& mask, uint64_t real_index, bool unlocked, std::unordered_set<crypto::public_key> &valid_public_keys_cache) const
 {
   if (!unlocked) // don't add locked outs
     return false;
@@ -8350,16 +8367,18 @@ bool wallet2::tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_out
   if (std::find(outs.back().begin(), outs.back().end(), item) != outs.back().end()) // don't add duplicates
     return false;
   // check the keys are valid
-  if (!rct::isInMainSubgroup(rct::pk2rct(output_public_key)))
+  if (valid_public_keys_cache.find(output_public_key) == valid_public_keys_cache.end() && !rct::isInMainSubgroup(rct::pk2rct(output_public_key)))
   {
     MWARNING("Key " << output_public_key << " at index " << global_index << " is not in the main subgroup");
     return false;
   }
-  if (!rct::isInMainSubgroup(mask))
+  valid_public_keys_cache.insert(output_public_key);
+  if (valid_public_keys_cache.find(rct::rct2pk(mask)) == valid_public_keys_cache.end() && !rct::isInMainSubgroup(mask))
   {
     MWARNING("Commitment " << mask << " at index " << global_index << " is not in the main subgroup");
     return false;
   }
+  valid_public_keys_cache.insert(rct::rct2pk(mask));
 //  if (is_output_blackballed(output_public_key)) // don't add blackballed outputs
 //    return false;
   outs.back().push_back(item);
@@ -8404,6 +8423,7 @@ void wallet2::light_wallet_get_outs(std::vector<std::vector<tools::wallet2::get_
 
   MDEBUG("selected transfers size: " << selected_transfers.size());
 
+  std::unordered_set<crypto::public_key> valid_public_keys_cache;
   for(size_t idx: selected_transfers)
   { 
     // Create new index
@@ -8455,7 +8475,7 @@ void wallet2::light_wallet_get_outs(std::vector<std::vector<tools::wallet2::get_
       if(!light_wallet_parse_rct_str(ores.amount_outs[amount_key].outputs[i].rct, tx_public_key, 0, mask, rct_commit, false))
         rct_commit = rct::zeroCommit(td.amount());
       
-      if (tx_add_fake_output(outs, global_index, tx_public_key, rct_commit, td.m_global_output_index, true)) {
+      if (tx_add_fake_output(outs, global_index, tx_public_key, rct_commit, td.m_global_output_index, true, valid_public_keys_cache)) {
         MDEBUG("added fake output " << ores.amount_outs[amount_key].outputs[i].public_key);
         MDEBUG("index " << global_index);
       }
@@ -8492,12 +8512,12 @@ std::pair<std::set<uint64_t>, size_t> outs_unique(const std::vector<std::vector<
   return std::make_pair(std::move(unique), total);
 }
 
-void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, bool rct)
+void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, bool rct, std::unordered_set<crypto::public_key> &valid_public_keys_cache)
 {
   std::vector<uint64_t> rct_offsets;
   for (size_t attempts = 3; attempts > 0; --attempts)
   {
-    get_outs(outs, selected_transfers, fake_outputs_count, rct_offsets);
+    get_outs(outs, selected_transfers, fake_outputs_count, rct_offsets, valid_public_keys_cache);
 
     if (!rct)
       return;
@@ -8519,7 +8539,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
   THROW_WALLET_EXCEPTION(error::wallet_internal_error, tr("Transaction sanity check failed"));
 }
 
-void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets)
+void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets, std::unordered_set<crypto::public_key> &valid_public_keys_cache)
 {
   LOG_PRINT_L2("fake_outputs_count: " << fake_outputs_count);
   outs.clear();
@@ -8563,6 +8583,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
     cryptonote::COMMAND_RPC_GET_OUTPUT_HISTOGRAM::request req_t = AUTO_VAL_INIT(req_t);
     cryptonote::COMMAND_RPC_GET_OUTPUT_HISTOGRAM::response resp_t = AUTO_VAL_INIT(resp_t);
     // request histogram for all outputs, except 0 if we have the rct distribution
+    req_t.amounts.reserve(selected_transfers.size());
     for(size_t idx: selected_transfers)
       if (!m_transfers[idx].is_rct() || !has_rct_distribution)
         req_t.amounts.push_back(m_transfers[idx].is_rct() ? 0 : m_transfers[idx].amount());
@@ -8590,6 +8611,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
     {
       cryptonote::COMMAND_RPC_GET_OUTPUT_DISTRIBUTION::request req_t = AUTO_VAL_INIT(req_t);
       cryptonote::COMMAND_RPC_GET_OUTPUT_DISTRIBUTION::response resp_t = AUTO_VAL_INIT(resp_t);
+      req_t.amounts.reserve(req_t.amounts.size() + selected_transfers.size());
       for(size_t idx: selected_transfers)
         req_t.amounts.push_back(m_transfers[idx].is_rct() ? 0 : m_transfers[idx].amount());
       std::sort(req_t.amounts.begin(), req_t.amounts.end());
@@ -8636,6 +8658,25 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       }
     }
 
+    std::vector<crypto::key_image> ring_key_images;
+    ring_key_images.reserve(selected_transfers.size());
+    std::unordered_map<crypto::key_image, std::vector<uint64_t>> existing_rings;
+    for(size_t idx: selected_transfers)
+    {
+      const transfer_details &td = m_transfers[idx];
+      if (td.m_key_image_known && !td.m_key_image_partial)
+        ring_key_images.push_back(td.m_key_image);
+    }
+    if (!ring_key_images.empty())
+    {
+      std::vector<std::vector<uint64_t>> all_outs;
+      if (get_rings(get_ringdb_key(), ring_key_images, all_outs))
+      {
+        for (size_t i = 0; i < ring_key_images.size(); ++i)
+          existing_rings[ring_key_images[i]] = std::move(all_outs[i]);
+      }
+    }
+
     // we ask for more, to have spares if some outputs are still locked
     size_t base_requested_outputs_count = (size_t)((fake_outputs_count + 1) * 1.5 + 1);
     LOG_PRINT_L2("base_requested_outputs_count: " << base_requested_outputs_count);
@@ -8649,6 +8690,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       gamma.reset(new gamma_picker(rct_offsets));
 
     size_t num_selected_transfers = 0;
+    req.outputs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW));
+    daemon_resp.outs.reserve(selected_transfers.size() * (base_requested_outputs_count + CRYPTONOTE_MINED_MONEY_UNLOCK_WINDOW));
     for(size_t idx: selected_transfers)
     {
       ++num_selected_transfers;
@@ -8758,9 +8801,12 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       // if we have a known ring, use it
       if (td.m_key_image_known && !td.m_key_image_partial)
       {
-        std::vector<uint64_t> ring;
-        if (get_ring(get_ringdb_key(), td.m_key_image, ring))
+
+        const auto it = existing_rings.find(td.m_key_image);
+        const bool has_ring = it != existing_rings.end();
+        if (has_ring)
         {
+          const std::vector<uint64_t> &ring = it->second;
           MINFO("This output has a known ring, reusing (size " << ring.size() << ")");
           THROW_WALLET_EXCEPTION_IF(ring.size() > fake_outputs_count + 1, error::wallet_internal_error,
               "An output in this transaction was previously spent on another chain with ring size " +
@@ -9018,9 +9064,10 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       // then pick outs from an existing ring, if any
       if (td.m_key_image_known && !td.m_key_image_partial)
       {
-        std::vector<uint64_t> ring;
-        if (get_ring(get_ringdb_key(), td.m_key_image, ring))
+        const auto it = existing_rings.find(td.m_key_image);
+        if (it != existing_rings.end())
         {
+          const std::vector<uint64_t> &ring = it->second;
           for (uint64_t out: ring)
           {
             if (out < num_outs)
@@ -9034,7 +9081,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
                   if (req.outputs[i].index == out)
                   {
                     LOG_PRINT_L2("Index " << i << "/" << requested_outputs_count << ": idx " << req.outputs[i].index << " (real " << td.m_global_output_index << "), unlocked " << daemon_resp.outs[i].unlocked << ", key " << daemon_resp.outs[i].key << " (from existing ring)");
-                    tx_add_fake_output(outs, req.outputs[i].index, daemon_resp.outs[i].key, daemon_resp.outs[i].mask, td.m_global_output_index, daemon_resp.outs[i].unlocked);
+                    tx_add_fake_output(outs, req.outputs[i].index, daemon_resp.outs[i].key, daemon_resp.outs[i].mask, td.m_global_output_index, daemon_resp.outs[i].unlocked, valid_public_keys_cache);
                     found = true;
                     break;
                   }
@@ -9059,7 +9106,7 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
       {
         size_t i = base + order[o];
         LOG_PRINT_L2("Index " << i << "/" << requested_outputs_count << ": idx " << req.outputs[i].index << " (real " << td.m_global_output_index << "), unlocked " << daemon_resp.outs[i].unlocked << ", key " << daemon_resp.outs[i].key);
-        tx_add_fake_output(outs, req.outputs[i].index, daemon_resp.outs[i].key, daemon_resp.outs[i].mask, td.m_global_output_index, daemon_resp.outs[i].unlocked);
+        tx_add_fake_output(outs, req.outputs[i].index, daemon_resp.outs[i].key, daemon_resp.outs[i].mask, td.m_global_output_index, daemon_resp.outs[i].unlocked, valid_public_keys_cache);
       }
       if (outs.back().size() < fake_outputs_count + 1)
       {
@@ -9087,6 +9134,8 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
   }
 
   // save those outs in the ringdb for reuse
+  std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> rings;
+  rings.reserve(selected_transfers.size());
   for (size_t i = 0; i < selected_transfers.size(); ++i)
   {
     const size_t idx = selected_transfers[i];
@@ -9096,14 +9145,15 @@ void wallet2::get_outs(std::vector<std::vector<tools::wallet2::get_outs_entry>>
     ring.reserve(outs[i].size());
     for (const auto &e: outs[i])
       ring.push_back(std::get<0>(e));
-    if (!set_ring(td.m_key_image, ring, false))
-      MERROR("Failed to set ring for " << td.m_key_image);
+    rings.push_back(std::make_pair(td.m_key_image, std::move(ring)));
   }
+  if (!set_rings(rings, false))
+    MERROR("Failed to set rings");
 }
 
 template<typename T>
 void wallet2::transfer_selected(const std::vector<cryptonote::tx_destination_entry>& dsts, const std::vector<size_t>& selected_transfers, size_t fake_outputs_count,
-  std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs,
+  std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, std::unordered_set<crypto::public_key> &valid_public_keys_cache,
   uint64_t unlock_time, uint64_t fee, const std::vector<uint8_t>& extra, T destination_split_strategy, const tx_dust_policy& dust_policy, cryptonote::transaction& tx, pending_tx &ptx)
 {
   using namespace cryptonote;
@@ -9140,7 +9190,7 @@ void wallet2::transfer_selected(const std::vector<cryptonote::tx_destination_ent
     THROW_WALLET_EXCEPTION_IF(subaddr_account != m_transfers[*i].m_subaddr_index.major, error::wallet_internal_error, "the tx uses funds from multiple accounts");
 
   if (outs.empty())
-    get_outs(outs, selected_transfers, fake_outputs_count, false); // may throw
+    get_outs(outs, selected_transfers, fake_outputs_count, false, valid_public_keys_cache); // may throw
 
   //prepare inputs
   LOG_PRINT_L2("preparing outputs");
@@ -9263,7 +9313,7 @@ void wallet2::transfer_selected(const std::vector<cryptonote::tx_destination_ent
 }
 
 void wallet2::transfer_selected_rct(std::vector<cryptonote::tx_destination_entry> dsts, const std::vector<size_t>& selected_transfers, size_t fake_outputs_count,
-  std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs,
+  std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, std::unordered_set<crypto::public_key> &valid_public_keys_cache,
   uint64_t unlock_time, uint64_t fee, const std::vector<uint8_t>& extra, cryptonote::transaction& tx, pending_tx &ptx, const rct::RCTConfig &rct_config)
 {
   using namespace cryptonote;
@@ -9357,7 +9407,7 @@ void wallet2::transfer_selected_rct(std::vector<cryptonote::tx_destination_entry
     THROW_WALLET_EXCEPTION_IF(subaddr_account != m_transfers[*i].m_subaddr_index.major, error::wallet_internal_error, "the tx uses funds from multiple accounts");
 
   if (outs.empty())
-    get_outs(outs, selected_transfers, fake_outputs_count, all_rct); // may throw
+    get_outs(outs, selected_transfers, fake_outputs_count, all_rct, valid_public_keys_cache); // may throw
 
   //prepare inputs
   LOG_PRINT_L2("preparing outputs");
@@ -10240,6 +10290,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
     rct::RangeProofPaddedBulletproof,
     bulletproof_plus ? 4 : 3
   };
+  std::unordered_set<crypto::public_key> valid_public_keys_cache;
 
   const uint64_t base_fee  = get_base_fee();
   const uint64_t fee_multiplier = get_fee_multiplier(priority, get_fee_algorithm());
@@ -10585,10 +10636,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
       LOG_PRINT_L2("Trying to create a tx now, with " << tx.dsts.size() << " outputs and " <<
         tx.selected_transfers.size() << " inputs");
       if (use_rct)
-        transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+        transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
           test_tx, test_ptx, rct_config);
       else
-        transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+        transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
           detail::digit_split_strategy, tx_dust_policy(::config::DEFAULT_DUST_THRESHOLD), test_tx, test_ptx);
       auto txBlob = t_serializable_object_to_blob(test_ptx.tx);
       needed_fee = calculate_fee(use_per_byte_fee, test_ptx.tx, txBlob.size(), base_fee, fee_multiplier, fee_quantization_mask);
@@ -10628,10 +10679,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
         LOG_PRINT_L2("We made a tx, adjusting fee and saving it, we need " << print_money(needed_fee) << " and we have " << print_money(test_ptx.fee));
         while (needed_fee > test_ptx.fee) {
           if (use_rct)
-            transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+            transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
               test_tx, test_ptx, rct_config);
           else
-            transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+            transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
               detail::digit_split_strategy, tx_dust_policy(::config::DEFAULT_DUST_THRESHOLD), test_tx, test_ptx);
           txBlob = t_serializable_object_to_blob(test_ptx.tx);
           needed_fee = calculate_fee(use_per_byte_fee, test_ptx.tx, txBlob.size(), base_fee, fee_multiplier, fee_quantization_mask);
@@ -10697,6 +10748,7 @@ skip_tx:
                             tx.selected_transfers,      /* const std::list<size_t> selected_transfers */
                             fake_outs_count,            /* CONST size_t fake_outputs_count, */
                             tx.outs,                    /* MOD   std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, */
+                            valid_public_keys_cache,
                             unlock_time,                /* CONST uint64_t unlock_time,  */
                             tx.needed_fee,              /* CONST uint64_t fee, */
                             extra,                      /* const std::vector<uint8_t>& extra, */
@@ -10708,6 +10760,7 @@ skip_tx:
                         tx.selected_transfers,
                         fake_outs_count,
                         tx.outs,
+                        valid_public_keys_cache,
                         unlock_time,
                         tx.needed_fee,
                         extra,
@@ -10827,6 +10880,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_all(uint64_t below
   THROW_WALLET_EXCEPTION_IF(tx_weight_one_ring > tx_weight_two_rings, error::wallet_internal_error, "Estimated tx weight with 1 input is larger than with 2 inputs!");
   const size_t tx_weight_per_ring = tx_weight_two_rings - tx_weight_one_ring;
   const uint64_t fractional_threshold = (fee_multiplier * base_fee * tx_weight_per_ring) / (use_per_byte_fee ? 1 : 1024);
+  std::unordered_set<crypto::public_key> valid_public_keys_cache;
 
   THROW_WALLET_EXCEPTION_IF(unlocked_balance(subaddr_account, false) == 0, error::wallet_internal_error, "No unlocked balance in the specified account");
 
@@ -10908,6 +10962,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
   hw::device &hwdev = m_account.get_device();
   boost::unique_lock<hw::device> hwdev_lock (hwdev);
   hw::reset_mode rst(hwdev);  
+  std::unordered_set<crypto::public_key> valid_public_keys_cache;
 
   uint64_t accumulated_fee, accumulated_outputs, accumulated_change;
   struct TX {
@@ -11010,10 +11065,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
       LOG_PRINT_L2("Trying to create a tx now, with " << tx.dsts.size() << " destinations and " <<
         tx.selected_transfers.size() << " outputs");
       if (use_rct)
-        transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+        transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
           test_tx, test_ptx, rct_config);
       else
-        transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+        transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
           detail::digit_split_strategy, tx_dust_policy(::config::DEFAULT_DUST_THRESHOLD), test_tx, test_ptx);
       auto txBlob = t_serializable_object_to_blob(test_ptx.tx);
       needed_fee = calculate_fee(use_per_byte_fee, test_ptx.tx, txBlob.size(), base_fee, fee_multiplier, fee_quantization_mask);
@@ -11047,10 +11102,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
           dt.amount = dt_amount + dt_residue;
         }
         if (use_rct)
-          transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra, 
+          transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra, 
             test_tx, test_ptx, rct_config);
         else
-          transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, unlock_time, needed_fee, extra,
+          transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, outs, valid_public_keys_cache, unlock_time, needed_fee, extra,
             detail::digit_split_strategy, tx_dust_policy(::config::DEFAULT_DUST_THRESHOLD), test_tx, test_ptx);
         txBlob = t_serializable_object_to_blob(test_ptx.tx);
         needed_fee = calculate_fee(use_per_byte_fee, test_ptx.tx, txBlob.size(), base_fee, fee_multiplier, fee_quantization_mask);
@@ -11086,10 +11141,10 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
     cryptonote::transaction test_tx;
     pending_tx test_ptx;
     if (use_rct) {
-      transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, tx.outs, unlock_time, tx.needed_fee, extra,
+      transfer_selected_rct(tx.dsts, tx.selected_transfers, fake_outs_count, tx.outs, valid_public_keys_cache, unlock_time, tx.needed_fee, extra,
         test_tx, test_ptx, rct_config);
     } else {
-      transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, tx.outs, unlock_time, tx.needed_fee, extra,
+      transfer_selected(tx.dsts, tx.selected_transfers, fake_outs_count, tx.outs, valid_public_keys_cache, unlock_time, tx.needed_fee, extra,
         detail::digit_split_strategy, tx_dust_policy(::config::DEFAULT_DUST_THRESHOLD), test_tx, test_ptx);
     }
     auto txBlob = t_serializable_object_to_blob(test_ptx.tx);
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index f642679d4..72c8e8545 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -951,10 +951,10 @@ private:
     uint64_t unlocked_balance_all(bool strict, uint64_t *blocks_to_unlock = NULL, uint64_t *time_to_unlock = NULL);
     template<typename T>
     void transfer_selected(const std::vector<cryptonote::tx_destination_entry>& dsts, const std::vector<size_t>& selected_transfers, size_t fake_outputs_count,
-      std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs,
+      std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, std::unordered_set<crypto::public_key> &valid_public_keys_cache,
       uint64_t unlock_time, uint64_t fee, const std::vector<uint8_t>& extra, T destination_split_strategy, const tx_dust_policy& dust_policy, cryptonote::transaction& tx, pending_tx &ptx);
     void transfer_selected_rct(std::vector<cryptonote::tx_destination_entry> dsts, const std::vector<size_t>& selected_transfers, size_t fake_outputs_count,
-      std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs,
+      std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, std::unordered_set<crypto::public_key> &valid_public_keys_cache,
       uint64_t unlock_time, uint64_t fee, const std::vector<uint8_t>& extra, cryptonote::transaction& tx, pending_tx &ptx, const rct::RCTConfig &rct_config);
 
     void commit_tx(pending_tx& ptx_vector);
@@ -1505,7 +1505,9 @@ private:
     const std::string get_ring_database() const { return m_ring_database; }
     bool get_ring(const crypto::key_image &key_image, std::vector<uint64_t> &outs);
     bool get_rings(const crypto::hash &txid, std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &outs);
+    bool get_rings(const crypto::chacha_key &key, const std::vector<crypto::key_image> &key_images, std::vector<std::vector<uint64_t>> &outs);
     bool set_ring(const crypto::key_image &key_image, const std::vector<uint64_t> &outs, bool relative);
+    bool set_rings(const std::vector<std::pair<crypto::key_image, std::vector<uint64_t>>> &rings, bool relative);
     bool unset_ring(const std::vector<crypto::key_image> &key_images);
     bool unset_ring(const crypto::hash &txid);
     bool find_and_save_rings(bool force = true);
@@ -1633,9 +1635,9 @@ private:
     void set_unspent(size_t idx);
     bool is_spent(const transfer_details &td, bool strict = true) const;
     bool is_spent(size_t idx, bool strict = true) const;
-    void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, bool rct);
-    void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets);
-    bool tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& tx_public_key, const rct::key& mask, uint64_t real_index, bool unlocked) const;
+    void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, bool rct, std::unordered_set<crypto::public_key> &valid_public_keys_cache);
+    void get_outs(std::vector<std::vector<get_outs_entry>> &outs, const std::vector<size_t> &selected_transfers, size_t fake_outputs_count, std::vector<uint64_t> &rct_offsets, std::unordered_set<crypto::public_key> &valid_public_keys_cache);
+    bool tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& tx_public_key, const rct::key& mask, uint64_t real_index, bool unlocked, std::unordered_set<crypto::public_key> &valid_public_keys_cache) const;
     bool should_pick_a_second_output(bool use_rct, size_t n_transfers, const std::vector<size_t> &unused_transfers_indices, const std::vector<size_t> &unused_dust_indices) const;
     std::vector<size_t> get_only_rct(const std::vector<size_t> &unused_dust_indices, const std::vector<size_t> &unused_transfers_indices) const;
     void scan_output(const cryptonote::transaction &tx, bool miner_tx, const crypto::public_key &tx_pub_key, size_t i, tx_scan_info_t &tx_scan_info, int &num_vouts_received, std::unordered_map<cryptonote::subaddress_index, uint64_t> &tx_money_got_in_outs, std::vector<size_t> &outs, bool pool);