From bf31447e9bd9e424538abc8f4cb57bd133f439ed Mon Sep 17 00:00:00 2001
From: moneromooo-monero <moneromooo-monero@users.noreply.github.com>
Date: Wed, 31 Oct 2018 13:52:16 +0000
Subject: [PATCH] tx_pool: speed up take_tx for transactions from blocks

This happens for every historical tx when syncing, and the
unnecessary parsing is actually showing up on profile.
Since these are kept cached for just one block, this does
not increase memory usage after syncing.
---
 src/cryptonote_core/tx_pool.cpp | 13 ++++++++++++-
 src/cryptonote_core/tx_pool.h   |  2 ++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/cryptonote_core/tx_pool.cpp b/src/cryptonote_core/tx_pool.cpp
index a31c9d3ed..19467aec7 100644
--- a/src/cryptonote_core/tx_pool.cpp
+++ b/src/cryptonote_core/tx_pool.cpp
@@ -247,6 +247,8 @@ namespace cryptonote
         memset(meta.padding, 0, sizeof(meta.padding));
         try
         {
+          if (kept_by_block)
+            m_parsed_tx_cache.insert(std::make_pair(id, tx));
           CRITICAL_REGION_LOCAL1(m_blockchain);
           LockedTXN lock(m_blockchain);
           m_blockchain.add_txpool_tx(id, blob, meta);
@@ -288,6 +290,8 @@ namespace cryptonote
 
       try
       {
+        if (kept_by_block)
+          m_parsed_tx_cache.insert(std::make_pair(id, tx));
         CRITICAL_REGION_LOCAL1(m_blockchain);
         LockedTXN lock(m_blockchain);
         m_blockchain.remove_txpool_tx(id);
@@ -468,7 +472,12 @@ namespace cryptonote
         return false;
       }
       cryptonote::blobdata txblob = m_blockchain.get_txpool_tx_blob(id);
-      if (!parse_and_validate_tx_from_blob(txblob, tx))
+      auto ci = m_parsed_tx_cache.find(id);
+      if (ci != m_parsed_tx_cache.end())
+      {
+        tx = ci->second;
+      }
+      else if (!parse_and_validate_tx_from_blob(txblob, tx))
       {
         MERROR("Failed to parse tx from txpool");
         return false;
@@ -911,6 +920,7 @@ namespace cryptonote
   {
     CRITICAL_REGION_LOCAL(m_transactions_lock);
     m_input_cache.clear();
+    m_parsed_tx_cache.clear();
     return true;
   }
   //---------------------------------------------------------------------------------
@@ -918,6 +928,7 @@ namespace cryptonote
   {
     CRITICAL_REGION_LOCAL(m_transactions_lock);
     m_input_cache.clear();
+    m_parsed_tx_cache.clear();
     return true;
   }
   //---------------------------------------------------------------------------------
diff --git a/src/cryptonote_core/tx_pool.h b/src/cryptonote_core/tx_pool.h
index 09d134d7b..6270a30bf 100644
--- a/src/cryptonote_core/tx_pool.h
+++ b/src/cryptonote_core/tx_pool.h
@@ -584,6 +584,8 @@ private:
     size_t m_txpool_weight;
 
     mutable std::unordered_map<crypto::hash, std::tuple<bool, tx_verification_context, uint64_t, crypto::hash>> m_input_cache;
+
+    std::unordered_map<crypto::hash, transaction> m_parsed_tx_cache;
   };
 }