Use actual batch size for resize estimates

And optimize import startup:

Remember start_height position during initial count_blocks pass
to avoid having to reread entire file again to arrive at start_height

src/blockchain_utilities/blockchain_import.cpp

@@ -230,11 +230,22 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
     return false;
   }
 
+  uint64_t start_height = 1, seek_height;
+  if (opt_resume)
+    start_height = core.get_blockchain_storage().get_current_blockchain_height();
+
+  seek_height = start_height;
   BootstrapFile bootstrap;
+  streampos pos;
   // BootstrapFile bootstrap(import_file_path);
-  uint64_t total_source_blocks = bootstrap.count_blocks(import_file_path);
+  uint64_t total_source_blocks = bootstrap.count_blocks(import_file_path, pos, seek_height);
   MINFO("bootstrap file last block number: " << total_source_blocks-1 << " (zero-based height)  total blocks: " << total_source_blocks);
 
+  if (total_source_blocks-1 <= start_height)
+  {
+    return false;
+  }
+
   std::cout << ENDL;
   std::cout << "Preparing to read blocks..." << ENDL;
   std::cout << ENDL;
@@ -259,11 +270,7 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
   block b;
   transaction tx;
   int quit = 0;
-  uint64_t bytes_read = 0;
-
-  uint64_t start_height = 1;
-  if (opt_resume)
-    start_height = core.get_blockchain_storage().get_current_blockchain_height();
+  uint64_t bytes_read;
 
   // Note that a new blockchain will start with block number 0 (total blocks: 1)
   // due to genesis block being added at initialization.
@@ -280,18 +287,35 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
 
   bool use_batch = opt_batch && !opt_verify;
 
-  if (use_batch)
-    core.get_blockchain_storage().get_db().batch_start(db_batch_size);
-
   MINFO("Reading blockchain from bootstrap file...");
   std::cout << ENDL;
 
   std::list<block_complete_entry> blocks;
 
-  // Within the loop, we skip to start_height before we start adding.
-  // TODO: Not a bottleneck, but we can use what's done in count_blocks() and
-  // only do the chunk size reads, skipping the chunk content reads until we're
-  // at start_height.
+  // Skip to start_height before we start adding.
+  {
+    bool q2 = false;
+    import_file.seekg(pos);
+    bytes_read = bootstrap.count_bytes(import_file, start_height-seek_height, h, q2);
+    if (q2)
+    {
+      quit = 2;
+      goto quitting;
+    }
+    h = start_height;
+  }
+
+  if (use_batch)
+  {
+    uint64_t bytes, h2;
+    bool q2;
+    pos = import_file.tellg();
+    bytes = bootstrap.count_bytes(import_file, db_batch_size, h2, q2);
+    if (import_file.eof())
+      import_file.clear();
+    import_file.seekg(pos);
+    core.get_blockchain_storage().get_db().batch_start(db_batch_size, bytes);
+  }
   while (! quit)
   {
     uint32_t chunk_size;
@@ -344,11 +368,6 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
     bytes_read += chunk_size;
     MDEBUG("Total bytes read: " << bytes_read);
 
-    if (h + NUM_BLOCKS_PER_CHUNK < start_height + 1)
-    {
-      h += NUM_BLOCKS_PER_CHUNK;
-      continue;
-    }
     if (h > block_stop)
     {
       std::cout << refresh_string << "block " << h-1
@@ -456,11 +475,16 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
           {
             if ((h-1) % db_batch_size == 0)
             {
+              uint64_t bytes, h2;
+              bool q2;
               std::cout << refresh_string;
               // zero-based height
               std::cout << ENDL << "[- batch commit at height " << h-1 << " -]" << ENDL;
               core.get_blockchain_storage().get_db().batch_stop();
-              core.get_blockchain_storage().get_db().batch_start(db_batch_size);
+              pos = import_file.tellg();
+              bytes = bootstrap.count_bytes(import_file, db_batch_size, h2, q2);
+              import_file.seekg(pos);
+              core.get_blockchain_storage().get_db().batch_start(db_batch_size, bytes);
               std::cout << ENDL;
               core.get_blockchain_storage().get_db().show_stats();
             }
@@ -477,6 +501,7 @@ int import_from_file(cryptonote::core& core, const std::string& import_file_path
     }
   } // while
 
+quitting:
   import_file.close();
 
   if (opt_verify)

src/blockchain_utilities/bootstrap_file.cpp

@@ -375,39 +375,15 @@ uint64_t BootstrapFile::seek_to_first_chunk(std::ifstream& import_file)
   return full_header_size;
 }
 
-uint64_t BootstrapFile::count_blocks(const std::string& import_file_path)
+uint64_t BootstrapFile::count_bytes(std::ifstream& import_file, uint64_t blocks, uint64_t& h, bool& quit)
 {
-  boost::filesystem::path raw_file_path(import_file_path);
-  boost::system::error_code ec;
-  if (!boost::filesystem::exists(raw_file_path, ec))
-  {
-    MFATAL("bootstrap file not found: " << raw_file_path);
-    throw std::runtime_error("Aborting");
-  }
-  std::ifstream import_file;
-  import_file.open(import_file_path, std::ios_base::binary | std::ifstream::in);
-
-  uint64_t h = 0;
-  if (import_file.fail())
-  {
-    MFATAL("import_file.open() fail");
-    throw std::runtime_error("Aborting");
-  }
-
-  uint64_t full_header_size; // 4 byte magic + length of header structures
-  full_header_size = seek_to_first_chunk(import_file);
-
-  MINFO("Scanning blockchain from bootstrap file...");
-  block b;
-  bool quit = false;
   uint64_t bytes_read = 0;
-  int progress_interval = 10;
-
+  uint32_t chunk_size;
+  char buf1[sizeof(chunk_size)];
   std::string str1;
-  char buf1[2048];
-  while (! quit)
+  h = 0;
+  while (1)
   {
-    uint32_t chunk_size;
     import_file.read(buf1, sizeof(chunk_size));
     if (!import_file) {
       std::cout << refresh_string;
@@ -415,15 +391,7 @@ uint64_t BootstrapFile::count_blocks(const std::string& import_file_path)
       quit = true;
       break;
     }
-    h += NUM_BLOCKS_PER_CHUNK;
-    if ((h-1) % progress_interval == 0)
-    {
-      std::cout << "\r" << "block height: " << h-1 <<
-        "    " <<
-        std::flush;
-    }
     bytes_read += sizeof(chunk_size);
-
     str1.assign(buf1, sizeof(chunk_size));
     if (! ::serialization::parse_binary(str1, chunk_size))
       throw std::runtime_error("Error in deserialization of chunk_size");
@@ -456,6 +424,64 @@ uint64_t BootstrapFile::count_blocks(const std::string& import_file_path)
       throw std::runtime_error("Aborting");
     }
     bytes_read += chunk_size;
+    h += NUM_BLOCKS_PER_CHUNK;
+    if (h >= blocks)
+      break;
+  }
+  return bytes_read;
+}
+
+uint64_t BootstrapFile::count_blocks(const std::string& import_file_path)
+{
+  streampos dummy_pos;
+  uint64_t dummy_height = 0;
+  return count_blocks(import_file_path, dummy_pos, dummy_height);
+}
+
+// If seek_height is non-zero on entry, return a stream position <= this height when finished.
+// And return the actual height corresponding to this position. Allows the caller to locate its
+// starting position without having to reread the entire file again.
+uint64_t BootstrapFile::count_blocks(const std::string& import_file_path, streampos &start_pos, uint64_t& seek_height)
+{
+  boost::filesystem::path raw_file_path(import_file_path);
+  boost::system::error_code ec;
+  if (!boost::filesystem::exists(raw_file_path, ec))
+  {
+    MFATAL("bootstrap file not found: " << raw_file_path);
+    throw std::runtime_error("Aborting");
+  }
+  std::ifstream import_file;
+  import_file.open(import_file_path, std::ios_base::binary | std::ifstream::in);
+
+  uint64_t start_height = seek_height;
+  uint64_t h = 0;
+  if (import_file.fail())
+  {
+    MFATAL("import_file.open() fail");
+    throw std::runtime_error("Aborting");
+  }
+
+  uint64_t full_header_size; // 4 byte magic + length of header structures
+  full_header_size = seek_to_first_chunk(import_file);
+
+  MINFO("Scanning blockchain from bootstrap file...");
+  bool quit = false;
+  uint64_t bytes_read = 0, blocks;
+  int progress_interval = 10;
+
+  while (! quit)
+  {
+    if (start_height && h + progress_interval >= start_height - 1)
+    {
+      start_height = 0;
+      start_pos = import_file.tellg();
+      seek_height = h;
+    }
+    bytes_read += count_bytes(import_file, progress_interval, blocks, quit);
+    h += blocks;
+    std::cout << "\r" << "block height: " << h-1 <<
+      "    " <<
+      std::flush;
 
     // std::cout << refresh_string;
     MDEBUG("Number bytes scanned: " << bytes_read);

src/blockchain_utilities/bootstrap_file.h

@@ -56,6 +56,8 @@ class BootstrapFile
 {
 public:
 
+  uint64_t count_bytes(std::ifstream& import_file, uint64_t blocks, uint64_t& h, bool& quit);
+  uint64_t count_blocks(const std::string& dir_path, streampos& start_pos, uint64_t& seek_height);
   uint64_t count_blocks(const std::string& dir_path);
   uint64_t seek_to_first_chunk(std::ifstream& import_file);