Merge pull request #1748

bed2d9f2 Get rid of directory lock (Howard Chu)
2e913676 Handle map resizes from other processes (Howard Chu)
bf1348b7 Can't cache num_txs or num_outputs either (Howard Chu)
dc53e9ee Add a few read txns to streamline (Howard Chu)

5 files changed, 97 insertions, 104 deletions

diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp
index 0a35325e4..96afdb0ea 100644
--- a/src/blockchain_db/lmdb/db_lmdb.cpp
+++ b/src/blockchain_db/lmdb/db_lmdb.cpp
@@ -377,7 +377,50 @@ void mdb_txn_safe::allow_new_txns()
   creation_gate.clear();
 }
 
+void lmdb_resized(MDB_env *env)
+{
+  mdb_txn_safe::prevent_new_txns();
+
+  MGINFO("LMDB map resize detected.");
+
+  MDB_envinfo mei;
+
+  mdb_env_info(env, &mei);
+  uint64_t old = mei.me_mapsize;
+
+  mdb_txn_safe::wait_no_active_txns();
+
+  int result = mdb_env_set_mapsize(env, 0);
+  if (result)
+    throw0(DB_ERROR(lmdb_error("Failed to set new mapsize: ", result).c_str()));
+
+  mdb_env_info(env, &mei);
+  uint64_t new_mapsize = mei.me_mapsize;
+
+  MGINFO("LMDB Mapsize increased." << "  Old: " << old / (1024 * 1024) << "MiB" << ", New: " << new_mapsize / (1024 * 1024) << "MiB");
+
+  mdb_txn_safe::allow_new_txns();
+}
 
+inline int lmdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **txn)
+{
+  int res = mdb_txn_begin(env, parent, flags, txn);
+  if (res == MDB_MAP_RESIZED) {
+    lmdb_resized(env);
+    res = mdb_txn_begin(env, parent, flags, txn);
+  }
+  return res;
+}
+
+inline int lmdb_txn_renew(MDB_txn *txn)
+{
+  int res = mdb_txn_renew(txn);
+  if (res == MDB_MAP_RESIZED) {
+    lmdb_resized(mdb_txn_env(txn));
+    res = mdb_txn_renew(txn);
+  }
+  return res;
+}
 
 void BlockchainLMDB::do_resize(uint64_t increase_size)
 {
@@ -561,7 +604,7 @@ uint64_t BlockchainLMDB::get_estimated_batch_size(uint64_t batch_num_blocks) con
   {
     LOG_PRINT_L1("No existing blocks to check for average block size");
   }
-  else if (m_cum_count)
+  else if (m_cum_count >= num_prev_blocks)
   {
     avg_block_size = m_cum_size / m_cum_count;
     LOG_PRINT_L1("average block size across recent " << m_cum_count << " blocks: " << avg_block_size);
@@ -570,6 +613,9 @@ uint64_t BlockchainLMDB::get_estimated_batch_size(uint64_t batch_num_blocks) con
   }
   else
   {
+    MDB_txn *rtxn;
+    mdb_txn_cursors *rcurs;
+    block_rtxn_start(&rtxn, &rcurs);
     for (uint64_t block_num = block_start; block_num <= block_stop; ++block_num)
     {
       uint32_t block_size = get_block_size(block_num);
@@ -578,6 +624,7 @@ uint64_t BlockchainLMDB::get_estimated_batch_size(uint64_t batch_num_blocks) con
       // some blocks were to be skipped for being outliers.
       ++num_blocks_used;
     }
+    block_rtxn_stop();
     avg_block_size = total_block_size / num_blocks_used;
     LOG_PRINT_L1("average block size across recent " << num_blocks_used << " blocks: " << avg_block_size);
   }
@@ -702,7 +749,7 @@ uint64_t BlockchainLMDB::add_transaction_data(const crypto::hash& blk_hash, cons
   uint64_t m_height = height();
 
   int result;
-  uint64_t tx_id = m_num_txs;
+  uint64_t tx_id = num_txs();
 
   CURSOR(txs)
   CURSOR(tx_indices)
@@ -735,7 +782,6 @@ uint64_t BlockchainLMDB::add_transaction_data(const crypto::hash& blk_hash, cons
   if (result)
     throw0(DB_ERROR(lmdb_error("Failed to add tx blob to db transaction: ", result).c_str()));
 
-  m_num_txs++;
   return tx_id;
 }
 
@@ -783,8 +829,6 @@ void BlockchainLMDB::remove_transaction_data(const crypto::hash& tx_hash, const
   // Don't delete the tx_indices entry until the end, after we're done with val_tx_id
   if (mdb_cursor_del(m_cur_tx_indices, 0))
       throw1(DB_ERROR("Failed to add removal of tx index to db transaction"));
-
-  m_num_txs--;
 }
 
 uint64_t BlockchainLMDB::add_output(const crypto::hash& tx_hash,
@@ -797,6 +841,7 @@ uint64_t BlockchainLMDB::add_output(const crypto::hash& tx_hash,
   check_open();
   mdb_txn_cursors *m_cursors = &m_wcursors;
   uint64_t m_height = height();
+  uint64_t m_num_outputs = num_outputs();
 
   int result = 0;
 
@@ -849,7 +894,6 @@ uint64_t BlockchainLMDB::add_output(const crypto::hash& tx_hash,
   if ((result = mdb_cursor_put(m_cur_output_amounts, &val_amount, &data, MDB_APPENDDUP)))
       throw0(DB_ERROR(lmdb_error("Failed to add output pubkey to db transaction: ", result).c_str()));
 
-  m_num_outputs++;
   return ok.amount_index;
 }
 
@@ -934,8 +978,6 @@ void BlockchainLMDB::remove_output(const uint64_t amount, const uint64_t& out_in
   result = mdb_cursor_del(m_cur_output_amounts, 0);
   if (result)
     throw0(DB_ERROR(lmdb_error(std::string("Error deleting amount for output index ").append(boost::lexical_cast<std::string>(out_index).append(": ")).c_str(), result).c_str()));
-
-  m_num_outputs--;
 }
 
 void BlockchainLMDB::add_spent_key(const crypto::key_image& k_image)
@@ -1000,7 +1042,7 @@ tx_out BlockchainLMDB::output_from_blob(const blobdata& blob) const
 
 void BlockchainLMDB::check_open() const
 {
-  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+//  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
   if (!m_open)
     throw0(DB_ERROR("DB operation attempted on a not-open DB instance"));
 }
@@ -1155,16 +1197,6 @@ void BlockchainLMDB::open(const std::string& filename, const int mdb_flags)
   LOG_PRINT_L2("Setting m_height to: " << db_stats.ms_entries);
   uint64_t m_height = db_stats.ms_entries;
 
-  // get and keep current number of txs
-  if ((result = mdb_stat(txn, m_txs, &db_stats)))
-    throw0(DB_ERROR(lmdb_error("Failed to query m_txs: ", result).c_str()));
-  m_num_txs = db_stats.ms_entries;
-
-  // get and keep current number of outputs
-  if ((result = mdb_stat(txn, m_output_txs, &db_stats)))
-    throw0(DB_ERROR(lmdb_error("Failed to query m_output_txs: ", result).c_str()));
-  m_num_outputs = db_stats.ms_entries;
-
   bool compatible = true;
 
   MDB_val_copy<const char*> k("version");
@@ -1270,7 +1302,7 @@ void BlockchainLMDB::reset()
   check_open();
 
   mdb_txn_safe txn;
-  if (auto result = mdb_txn_begin(m_env, NULL, 0, txn))
+  if (auto result = lmdb_txn_begin(m_env, NULL, 0, txn))
     throw0(DB_ERROR(lmdb_error("Failed to create a transaction for the db: ", result).c_str()));
 
   if (auto result = mdb_drop(txn, m_blocks, 0))
@@ -1304,7 +1336,6 @@ void BlockchainLMDB::reset()
     throw0(DB_ERROR(lmdb_error("Failed to write version to database: ", result).c_str()));
 
   txn.commit();
-  m_num_outputs = 0;
   m_cum_size = 0;
   m_cum_count = 0;
 }
@@ -1354,7 +1385,7 @@ void BlockchainLMDB::unlock()
     txn_ptr = m_write_txn; \
   else \
   { \
-    if (auto mdb_res = mdb_txn_begin(m_env, NULL, flags, auto_txn)) \
+    if (auto mdb_res = lmdb_txn_begin(m_env, NULL, flags, auto_txn)) \
       throw0(DB_ERROR(lmdb_error(std::string("Failed to create a transaction for the db in ")+__FUNCTION__+": ", mdb_res).c_str())); \
   } \
 
@@ -1388,7 +1419,7 @@ void BlockchainLMDB::unlock()
     txn_ptr = m_write_txn; \
   else \
   { \
-    if (auto mdb_res = mdb_txn_begin(m_env, NULL, flags, auto_txn)) \
+    if (auto mdb_res = lmdb_txn_begin(m_env, NULL, flags, auto_txn)) \
       throw0(DB_ERROR(lmdb_error(std::string("Failed to create a transaction for the db in ")+__FUNCTION__+": ", mdb_res).c_str())); \
   } \
 
@@ -1714,6 +1745,34 @@ uint64_t BlockchainLMDB::height() const
   return db_stats.ms_entries;
 }
 
+uint64_t BlockchainLMDB::num_txs() const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+  TXN_PREFIX_RDONLY();
+  int result;
+
+  // get current height
+  MDB_stat db_stats;
+  if ((result = mdb_stat(m_txn, m_txs, &db_stats)))
+    throw0(DB_ERROR(lmdb_error("Failed to query m_txs: ", result).c_str()));
+  return db_stats.ms_entries;
+}
+
+uint64_t BlockchainLMDB::num_outputs() const
+{
+  LOG_PRINT_L3("BlockchainLMDB::" << __func__);
+  check_open();
+  TXN_PREFIX_RDONLY();
+  int result;
+
+  // get current height
+  MDB_stat db_stats;
+  if ((result = mdb_stat(m_txn, m_output_txs, &db_stats)))
+    throw0(DB_ERROR(lmdb_error("Failed to query m_output_txs: ", result).c_str()));
+  return db_stats.ms_entries;
+}
+
 bool BlockchainLMDB::tx_exists(const crypto::hash& h) const
 {
   LOG_PRINT_L3("BlockchainLMDB::" << __func__);
@@ -2279,7 +2338,7 @@ bool BlockchainLMDB::batch_start(uint64_t batch_num_blocks)
   m_write_batch_txn = new mdb_txn_safe();
 
   // NOTE: need to make sure it's destroyed properly when done
-  if (auto mdb_res = mdb_txn_begin(m_env, NULL, 0, *m_write_batch_txn))
+  if (auto mdb_res = lmdb_txn_begin(m_env, NULL, 0, *m_write_batch_txn))
   {
     delete m_write_batch_txn;
     m_write_batch_txn = nullptr;
@@ -2398,12 +2457,12 @@ bool BlockchainLMDB::block_rtxn_start(MDB_txn **mtxn, mdb_txn_cursors **mcur) co
     m_tinfo.reset(new mdb_threadinfo);
     memset(&m_tinfo->m_ti_rcursors, 0, sizeof(m_tinfo->m_ti_rcursors));
     memset(&m_tinfo->m_ti_rflags, 0, sizeof(m_tinfo->m_ti_rflags));
-    if (auto mdb_res = mdb_txn_begin(m_env, NULL, MDB_RDONLY, &m_tinfo->m_ti_rtxn))
+    if (auto mdb_res = lmdb_txn_begin(m_env, NULL, MDB_RDONLY, &m_tinfo->m_ti_rtxn))
       throw0(DB_ERROR_TXN_START(lmdb_error("Failed to create a read transaction for the db: ", mdb_res).c_str()));
     ret = true;
   } else if (!m_tinfo->m_ti_rflags.m_rf_txn)
   {
-    if (auto mdb_res = mdb_txn_renew(m_tinfo->m_ti_rtxn))
+    if (auto mdb_res = lmdb_txn_renew(m_tinfo->m_ti_rtxn))
       throw0(DB_ERROR_TXN_START(lmdb_error("Failed to renew a read transaction for the db: ", mdb_res).c_str()));
     ret = true;
   }
@@ -2436,12 +2495,12 @@ void BlockchainLMDB::block_txn_start(bool readonly)
       m_tinfo.reset(new mdb_threadinfo);
       memset(&m_tinfo->m_ti_rcursors, 0, sizeof(m_tinfo->m_ti_rcursors));
       memset(&m_tinfo->m_ti_rflags, 0, sizeof(m_tinfo->m_ti_rflags));
-      if (auto mdb_res = mdb_txn_begin(m_env, NULL, MDB_RDONLY, &m_tinfo->m_ti_rtxn))
+      if (auto mdb_res = lmdb_txn_begin(m_env, NULL, MDB_RDONLY, &m_tinfo->m_ti_rtxn))
         throw0(DB_ERROR_TXN_START(lmdb_error("Failed to create a read transaction for the db: ", mdb_res).c_str()));
       didit = true;
     } else if (!m_tinfo->m_ti_rflags.m_rf_txn)
     {
-      if (auto mdb_res = mdb_txn_renew(m_tinfo->m_ti_rtxn))
+      if (auto mdb_res = lmdb_txn_renew(m_tinfo->m_ti_rtxn))
         throw0(DB_ERROR_TXN_START(lmdb_error("Failed to renew a read transaction for the db: ", mdb_res).c_str()));
       didit = true;
     }
@@ -2467,7 +2526,7 @@ void BlockchainLMDB::block_txn_start(bool readonly)
   {
     m_writer = boost::this_thread::get_id();
     m_write_txn = new mdb_txn_safe();
-    if (auto mdb_res = mdb_txn_begin(m_env, NULL, 0, *m_write_txn))
+    if (auto mdb_res = lmdb_txn_begin(m_env, NULL, 0, *m_write_txn))
     {
       delete m_write_txn;
       m_write_txn = nullptr;
@@ -2545,8 +2604,6 @@ uint64_t BlockchainLMDB::add_block(const block& blk, const size_t& block_size, c
     }
   }
 
-  uint64_t num_txs = m_num_txs;
-  uint64_t num_outputs = m_num_outputs;
   try
   {
     BlockchainDB::add_block(blk, block_size, cumulative_difficulty, coins_generated, txs);
@@ -2557,8 +2614,6 @@ uint64_t BlockchainLMDB::add_block(const block& blk, const size_t& block_size, c
   }
   catch (...)
   {
-    m_num_txs = num_txs;
-    m_num_outputs = num_outputs;
     block_txn_abort();
     throw;
   }
@@ -2573,8 +2628,6 @@ void BlockchainLMDB::pop_block(block& blk, std::vector<transaction>& txs)
 
   block_txn_start(false);
 
-  uint64_t num_txs = m_num_txs;
-  uint64_t num_outputs = m_num_outputs;
   try
   {
     BlockchainDB::pop_block(blk, txs);
@@ -2582,8 +2635,6 @@ void BlockchainLMDB::pop_block(block& blk, std::vector<transaction>& txs)
   }
   catch (...)
   {
-    m_num_txs = num_txs;
-    m_num_outputs = num_outputs;
 	block_txn_abort();
     throw;
   }
@@ -3257,8 +3308,6 @@ void BlockchainLMDB::migrate_0_1()
     lmdb_db_open(txn, LMDB_OUTPUT_AMOUNTS, MDB_INTEGERKEY | MDB_DUPSORT | MDB_DUPFIXED | MDB_CREATE, m_output_amounts, "Failed to open db handle for m_output_amounts");
     mdb_set_dupsort(txn, m_output_amounts, compare_uint64);
     txn.commit();
-    m_num_txs = 0;
-    m_num_outputs = 0;
   } while(0);
 
   do {
@@ -3329,12 +3378,9 @@ void BlockchainLMDB::migrate_0_1()
           throw0(DB_ERROR(lmdb_error("Failed to open a cursor for txs: ", result).c_str()));
         if (!i) {
           MDB_stat ms;
-          mdb_stat(txn, m_output_txs, &ms);
-          m_num_outputs = ms.ms_entries;
           mdb_stat(txn, m_txs, &ms);
-          m_num_txs = i = ms.ms_entries;
+          i = ms.ms_entries;
           if (i) {
-            m_num_txs = i;
             MDB_val_set(pk, "txblk");
             result = mdb_cursor_get(c_props, &pk, &k, MDB_SET);
             if (result)
diff --git a/src/blockchain_db/lmdb/db_lmdb.h b/src/blockchain_db/lmdb/db_lmdb.h
index e7faf8cdc..b4e3c7174 100644
--- a/src/blockchain_db/lmdb/db_lmdb.h
+++ b/src/blockchain_db/lmdb/db_lmdb.h
@@ -312,6 +312,9 @@ private:
 
   virtual void remove_spent_key(const crypto::key_image& k_image);
 
+  uint64_t num_txs() const;
+  uint64_t num_outputs() const;
+
   // Hard fork
   virtual void set_hard_fork_version(uint64_t height, uint8_t version);
   virtual uint8_t get_hard_fork_version(uint64_t height) const;
@@ -369,10 +372,8 @@ private:
 
   MDB_dbi m_properties;
 
-  uint64_t m_num_txs;
-  uint64_t m_num_outputs;
   mutable uint64_t m_cum_size;	// used in batch size estimation
-  mutable int m_cum_count;
+  mutable unsigned int m_cum_count;
   std::string m_folder;
   mdb_txn_safe* m_write_txn; // may point to either a short-lived txn or a batch txn
   mdb_txn_safe* m_write_batch_txn; // persist batch txn outside of BlockchainLMDB
diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp
index a81286632..d5fefffcd 100644
--- a/src/cryptonote_core/blockchain.cpp
+++ b/src/cryptonote_core/blockchain.cpp
@@ -1986,12 +1986,14 @@ bool Blockchain::find_blockchain_supplement(const std::list<crypto::hash>& qbloc
     return false;
   }
 
+  m_db->block_txn_start(true);
   resp.total_height = get_current_blockchain_height();
   size_t count = 0;
   for(size_t i = resp.start_height; i < resp.total_height && count < BLOCKS_IDS_SYNCHRONIZING_DEFAULT_COUNT; i++, count++)
   {
     resp.m_block_ids.push_back(m_db->get_block_hash_from_height(i));
   }
+  m_db->block_txn_stop();
   return true;
 }
 //------------------------------------------------------------------
@@ -2022,6 +2024,7 @@ bool Blockchain::find_blockchain_supplement(const uint64_t req_start_block, cons
     }
   }
 
+  m_db->block_txn_start(true);
   total_height = get_current_blockchain_height();
   size_t count = 0;
   for(size_t i = start_height; i < total_height && count < max_count; i++, count++)
@@ -2032,6 +2035,7 @@ bool Blockchain::find_blockchain_supplement(const uint64_t req_start_block, cons
     get_transactions(blocks.back().first.tx_hashes, blocks.back().second, mis);
     CHECK_AND_ASSERT_MES(!mis.size(), false, "internal error, transaction from block not found");
   }
+  m_db->block_txn_stop();
   return true;
 }
 //------------------------------------------------------------------
diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp
index b940dba3c..239ef5d84 100644
--- a/src/cryptonote_core/cryptonote_core.cpp
+++ b/src/cryptonote_core/cryptonote_core.cpp
@@ -219,40 +219,6 @@ namespace cryptonote
     return m_blockchain_storage.get_alternative_blocks_count();
   }
   //-----------------------------------------------------------------------------------------------
-  bool core::lock_db_directory(const boost::filesystem::path &path)
-  {
-    // boost doesn't like locking directories...
-    const boost::filesystem::path lock_path = path / ".daemon_lock";
-
-    try
-    {
-      // ensure the file exists
-      std::ofstream(lock_path.string(), std::ios::out).close();
-
-      db_lock = boost::interprocess::file_lock(lock_path.string().c_str());
-      LOG_PRINT_L1("Locking " << lock_path.string());
-      if (!db_lock.try_lock())
-      {
-        LOG_ERROR("Failed to lock " << lock_path.string());
-        return false;
-      }
-      return true;
-    }
-    catch (const std::exception &e)
-    {
-      LOG_ERROR("Error trying to lock " << lock_path.string() << ": " << e.what());
-      return false;
-    }
-  }
-  //-----------------------------------------------------------------------------------------------
-  bool core::unlock_db_directory()
-  {
-    db_lock.unlock();
-    db_lock = boost::interprocess::file_lock();
-    LOG_PRINT_L1("Blockchain directory successfully unlocked");
-    return true;
-  }
-  //-----------------------------------------------------------------------------------------------
   bool core::init(const boost::program_options::variables_map& vm, const cryptonote::test_options *test_options)
   {
     start_time = std::time(nullptr);
@@ -284,11 +250,6 @@ namespace cryptonote
     // make sure the data directory exists, and try to lock it
     CHECK_AND_ASSERT_MES (boost::filesystem::exists(folder) || boost::filesystem::create_directories(folder), false,
       std::string("Failed to create directory ").append(folder.string()).c_str());
-    if (!lock_db_directory (folder))
-    {
-      LOG_ERROR ("Failed to lock " << folder);
-      return false;
-    }
 
     // check for blockchain.bin
     try
@@ -440,7 +401,6 @@ namespace cryptonote
     m_miner.stop();
     m_mempool.deinit();
     m_blockchain_storage.deinit();
-    unlock_db_directory();
     return true;
   }
   //-----------------------------------------------------------------------------------------------
diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h
index fe1d11916..1463c2feb 100644
--- a/src/cryptonote_core/cryptonote_core.h
+++ b/src/cryptonote_core/cryptonote_core.h
@@ -763,24 +763,6 @@ namespace cryptonote
       */
      bool relay_txpool_transactions();
 
-     /**
-      * @brief locks a file in the BlockchainDB directory
-      *
-      * @param path the directory in which to place the file
-      *
-      * @return true if lock acquired successfully, otherwise false
-      */
-     bool lock_db_directory(const boost::filesystem::path &path);
-
-     /**
-      * @brief unlocks the db directory
-      *
-      * @note see lock_db_directory()
-      *
-      * @return true
-      */
-     bool unlock_db_directory();
-
      bool m_test_drop_download = true; //!< whether or not to drop incoming blocks (for testing)
 
      uint64_t m_test_drop_download_height = 0; //!< height under which to drop incoming blocks, if doing so