Speedup print_pool_stats

Since we're just counting txs, there's no reason to deserialize all the blobs.

src/cryptonote_core/cryptonote_core.cpp

@@ -1046,6 +1046,12 @@ namespace cryptonote
     return true;
   }
   //-----------------------------------------------------------------------------------------------
+  bool core::get_pool_transaction_stats(struct txpool_stats& stats) const
+  {
+    m_mempool.get_transaction_stats(stats);
+    return true;
+  }
+  //-----------------------------------------------------------------------------------------------
   bool core::get_pool_transaction(const crypto::hash &id, cryptonote::blobdata& tx) const
   {
     return m_mempool.get_transaction(id, tx);

src/cryptonote_core/cryptonote_core.h

@@ -410,6 +410,13 @@ namespace cryptonote
       */
      bool get_pool_transaction_hashes(std::vector<crypto::hash>& txs) const;
 
+     /**
+      * @copydoc tx_memory_pool::get_transactions
+      *
+      * @note see tx_memory_pool::get_transactions
+      */
+     bool get_pool_transaction_stats(struct txpool_stats& stats) const;
+
      /**
       * @copydoc tx_memory_pool::get_transaction
       *

src/cryptonote_core/tx_pool.cpp

@@ -546,6 +546,31 @@ namespace cryptonote
     });
   }
   //------------------------------------------------------------------
+  void tx_memory_pool::get_transaction_stats(struct txpool_stats& stats) const
+  {
+    CRITICAL_REGION_LOCAL(m_transactions_lock);
+    CRITICAL_REGION_LOCAL1(m_blockchain);
+    const uint64_t now = time(NULL);
+    stats.txs_total = m_blockchain.get_txpool_tx_count();
+    m_blockchain.for_all_txpool_txes([&stats, now](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
+      stats.bytes_total += meta.blob_size;
+      if (!stats.bytes_min || meta.blob_size < stats.bytes_min)
+        stats.bytes_min = meta.blob_size;
+      if (meta.blob_size > stats.bytes_max)
+        stats.bytes_max = meta.blob_size;
+      if (!meta.relayed)
+        stats.num_not_relayed++;
+      stats.fee_total += meta.fee;
+      if (!stats.oldest || meta.receive_time < stats.oldest)
+        stats.oldest = meta.receive_time;
+      if (meta.receive_time < now - 600)
+        stats.num_10m++;
+      if (meta.last_failed_height)
+        stats.num_failing++;
+      return true;
+    });
+  }
+  //------------------------------------------------------------------
   //TODO: investigate whether boolean return is appropriate
   bool tx_memory_pool::get_transactions_and_spent_keys_info(std::vector<tx_info>& tx_infos, std::vector<spent_key_image_info>& key_image_infos) const
   {

src/cryptonote_core/tx_pool.h

@@ -242,6 +242,13 @@ namespace cryptonote
      */
     void get_transaction_hashes(std::vector<crypto::hash>& txs) const;
 
+    /**
+     * @brief get a summary statistics of all transaction hashes in the pool
+     *
+     * @param stats return-by-reference the pool statistics
+     */
+    void get_transaction_stats(struct txpool_stats& stats) const;
+
     /**
      * @brief get information about all transactions and key images in the pool
      *