Pruning

The blockchain prunes seven eighths of prunable tx data.
This saves about two thirds of the blockchain size, while
keeping the node useful as a sync source for an eighth
of the blockchain.

No other data is currently pruned.

There are three ways to prune a blockchain:

- run monerod with --prune-blockchain
- run "prune_blockchain" in the monerod console
- run the monero-blockchain-prune utility

The first two will prune in place. Due to how LMDB works, this
will not reduce the blockchain size on disk. Instead, it will
mark parts of the file as free, so that future data will use
that free space, causing the file to not grow until free space
grows scarce.

The third way will create a second database, a pruned copy of
the original one. Since this is a new file, this one will be
smaller than the original one.

Once the database is pruned, it will stay pruned as it syncs.
That is, there is no need to use --prune-blockchain again, etc.

src/cryptonote_basic/blobdatatype.h

@@ -30,7 +30,11 @@
 
 #pragma once
 
+#include <string>
+#include "span.h"
+
 namespace cryptonote
 {
   typedef std::string blobdata;
+  typedef epee::span<const char> blobdata_ref;
 }

src/cryptonote_basic/connection_context.h

@@ -40,7 +40,7 @@ namespace cryptonote
   struct cryptonote_connection_context: public epee::net_utils::connection_context_base
   {
     cryptonote_connection_context(): m_state(state_before_handshake), m_remote_blockchain_height(0), m_last_response_height(0),
-        m_last_request_time(boost::posix_time::microsec_clock::universal_time()), m_callback_request_count(0), m_last_known_hash(crypto::null_hash) {}
+        m_last_request_time(boost::date_time::not_a_date_time), m_callback_request_count(0), m_last_known_hash(crypto::null_hash), m_pruning_seed(0), m_anchor(false) {}
 
     enum state
     {
@@ -59,6 +59,8 @@ namespace cryptonote
     boost::posix_time::ptime m_last_request_time;
     epee::copyable_atomic m_callback_request_count; //in debug purpose: problem with double callback rise
     crypto::hash m_last_known_hash;
+    uint32_t m_pruning_seed;
+    bool m_anchor;
     //size_t m_score;  TODO: add score calculations
   };
 
@@ -81,4 +83,23 @@ namespace cryptonote
     }    
   }
 
+  inline char get_protocol_state_char(cryptonote_connection_context::state s)
+  {
+    switch (s)
+    {
+    case cryptonote_connection_context::state_before_handshake:
+      return 'h';
+    case cryptonote_connection_context::state_synchronizing:
+      return 's';
+    case cryptonote_connection_context::state_standby:
+      return 'w';
+    case cryptonote_connection_context::state_idle:
+      return 'i';
+    case cryptonote_connection_context::state_normal:
+      return 'n';
+    default:
+      return 'u';
+    }
+  }
+
 }

src/cryptonote_basic/cryptonote_basic.h

@@ -201,9 +201,11 @@ namespace cryptonote
     mutable crypto::hash hash;
     mutable size_t blob_size;
 
+    bool pruned;
+
     transaction();
-    transaction(const transaction &t): transaction_prefix(t), hash_valid(false), blob_size_valid(false), signatures(t.signatures), rct_signatures(t.rct_signatures) { if (t.is_hash_valid()) { hash = t.hash; set_hash_valid(true); } if (t.is_blob_size_valid()) { blob_size = t.blob_size; set_blob_size_valid(true); } }
-    transaction &operator=(const transaction &t) { transaction_prefix::operator=(t); set_hash_valid(false); set_blob_size_valid(false); signatures = t.signatures; rct_signatures = t.rct_signatures; if (t.is_hash_valid()) { hash = t.hash; set_hash_valid(true); } if (t.is_blob_size_valid()) { blob_size = t.blob_size; set_blob_size_valid(true); } return *this; }
+    transaction(const transaction &t): transaction_prefix(t), hash_valid(false), blob_size_valid(false), signatures(t.signatures), rct_signatures(t.rct_signatures), pruned(t.pruned) { if (t.is_hash_valid()) { hash = t.hash; set_hash_valid(true); } if (t.is_blob_size_valid()) { blob_size = t.blob_size; set_blob_size_valid(true); } }
+    transaction &operator=(const transaction &t) { transaction_prefix::operator=(t); set_hash_valid(false); set_blob_size_valid(false); signatures = t.signatures; rct_signatures = t.rct_signatures; if (t.is_hash_valid()) { hash = t.hash; set_hash_valid(true); } if (t.is_blob_size_valid()) { blob_size = t.blob_size; set_blob_size_valid(true); } pruned = t.pruned; return *this; }
     virtual ~transaction();
     void set_null();
     void invalidate_hashes();
@@ -232,7 +234,7 @@ namespace cryptonote
         if (!signatures_not_expected && vin.size() != signatures.size())
           return false;
 
-        for (size_t i = 0; i < vin.size(); ++i)
+        if (!pruned) for (size_t i = 0; i < vin.size(); ++i)
         {
           size_t signature_size = get_signature_size(vin[i]);
           if (signatures_not_expected)
@@ -263,7 +265,7 @@ namespace cryptonote
           bool r = rct_signatures.serialize_rctsig_base(ar, vin.size(), vout.size());
           if (!r || !ar.stream().good()) return false;
           ar.end_object();
-          if (rct_signatures.type != rct::RCTTypeNull)
+          if (!pruned && rct_signatures.type != rct::RCTTypeNull)
           {
             ar.tag("rctsig_prunable");
             ar.begin_object();
@@ -274,6 +276,8 @@ namespace cryptonote
           }
         }
       }
+      if (!typename Archive<W>::is_saving())
+        pruned = false;
     END_SERIALIZE()
 
     template<bool W, template <bool> class Archive>
@@ -295,6 +299,8 @@ namespace cryptonote
           ar.end_object();
         }
       }
+      if (!typename Archive<W>::is_saving())
+        pruned = true;
       return true;
     }
 
@@ -322,6 +328,7 @@ namespace cryptonote
     rct_signatures.type = rct::RCTTypeNull;
     set_hash_valid(false);
     set_blob_size_valid(false);
+    pruned = false;
   }
 
   inline

src/cryptonote_basic/cryptonote_format_utils.cpp

@@ -196,6 +196,7 @@ namespace cryptonote
     bool r = tx.serialize_base(ba);
     CHECK_AND_ASSERT_MES(r, false, "Failed to parse transaction from blob");
     CHECK_AND_ASSERT_MES(expand_transaction_1(tx, true), false, "Failed to expand transaction data");
+    tx.invalidate_hashes();
     return true;
   }
   //---------------------------------------------------------------
@@ -225,6 +226,22 @@ namespace cryptonote
     return true;
   }
   //---------------------------------------------------------------
+  bool is_v1_tx(const blobdata_ref& tx_blob)
+  {
+    uint64_t version;
+    const char* begin = static_cast<const char*>(tx_blob.data());
+    const char* end = begin + tx_blob.size();
+    int read = tools::read_varint(begin, end, version);
+    if (read <= 0)
+      throw std::runtime_error("Internal error getting transaction version");
+    return version <= 1;
+  }
+  //---------------------------------------------------------------
+  bool is_v1_tx(const blobdata& tx_blob)
+  {
+    return is_v1_tx(blobdata_ref{tx_blob.data(), tx_blob.size()});
+  }
+  //---------------------------------------------------------------
   bool generate_key_image_helper(const account_keys& ack, const std::unordered_map<crypto::public_key, subaddress_index>& subaddresses, const crypto::public_key& out_key, const crypto::public_key& tx_public_key, const std::vector<crypto::public_key>& additional_tx_public_keys, size_t real_output_index, keypair& in_ephemeral, crypto::key_image& ki, hw::device &hwdev)
   {
     crypto::key_derivation recv_derivation = AUTO_VAL_INIT(recv_derivation);

src/cryptonote_basic/cryptonote_format_utils.h

@@ -53,6 +53,8 @@ namespace cryptonote
   bool parse_and_validate_tx_from_blob(const blobdata& tx_blob, transaction& tx, crypto::hash& tx_hash, crypto::hash& tx_prefix_hash);
   bool parse_and_validate_tx_from_blob(const blobdata& tx_blob, transaction& tx);
   bool parse_and_validate_tx_base_from_blob(const blobdata& tx_blob, transaction& tx);
+  bool is_v1_tx(const blobdata_ref& tx_blob);
+  bool is_v1_tx(const blobdata& tx_blob);
 
   template<typename T>
   bool find_tx_extra_field_by_type(const std::vector<tx_extra_field>& tx_extra_fields, T& field, size_t index = 0)