Cache transaction validation successes

src/main.cpp

@@ -1277,6 +1277,9 @@ int GetSpendHeight(const CCoinsViewCache& inputs)
     return pindexPrev->nHeight + 1;
 }
 
+static mrumap<uint256, unsigned int> cacheCheck(2 * MAX_BLOCK_SIZE / CTransaction().GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION));
+static boost::mutex cs_cacheCheck;
+
 namespace Consensus {
 bool CheckTxInputs(const CTransaction& tx, CValidationState& state, const CCoinsViewCache& inputs, int nSpendHeight)
 {
@@ -1331,6 +1334,17 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi
 {
     if (!tx.IsCoinBase())
     {
+        if (fScriptChecks) {
+            boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+            mrumap<uint256, unsigned int>::const_iterator iter = cacheCheck.find(tx.GetHash());
+            if (iter != cacheCheck.end()) {
+                // The following test relies on the fact that all script validation flags are softforks (i.e. an extra bit set cannot cause a false result to become true).
+                if ((iter->second & flags) == flags) {
+                    return true;
+                }
+            }
+        }
+
         if (!Consensus::CheckTxInputs(tx, state, inputs, GetSpendHeight(inputs)))
             return false;
 
@@ -1381,6 +1395,11 @@ bool CheckInputs(const CTransaction& tx, CValidationState &state, const CCoinsVi
         }
     }
 
+    if (cacheStore && fScriptChecks && pvChecks == NULL) {
+        boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+        cacheCheck.insert(tx.GetHash(), flags);
+    }
+
     return true;
 }
 
@@ -2101,6 +2120,13 @@ bool static ConnectTip(CValidationState &state, CBlockIndex *pindexNew, CBlock *
     BOOST_FOREACH(const CTransaction &tx, pblock->vtx) {
         SyncWithWallets(tx, pblock);
     }
+    // Erase block's transactions from the validation cache
+    {
+        boost::unique_lock<boost::mutex> lock(cs_cacheCheck);
+        BOOST_FOREACH(const CTransaction &tx, pblock->vtx) {
+            cacheCheck.erase(tx.GetHash());
+        }
+    }
 
     int64_t nTime6 = GetTimeMicros(); nTimePostConnect += nTime6 - nTime5; nTimeTotal += nTime6 - nTime1;
     LogPrint("bench", "  - Connect postprocess: %.2fms [%.2fs]\n", (nTime6 - nTime5) * 0.001, nTimePostConnect * 0.000001);

src/mruset.h

@@ -9,6 +9,10 @@
 #include <vector>
 #include <utility>
 
+#include <boost/multi_index_container.hpp>
+#include <boost/multi_index/ordered_index.hpp>
+#include <boost/multi_index/sequenced_index.hpp>
+
 /** STL-like set container that only keeps the most recent N elements. */
 template <typename T>
 class mruset
@@ -62,4 +66,60 @@ public:
     size_type max_size() const { return nMaxSize; }
 };
 
+/** STL-like map container that only keeps the most recent N elements. */
+template <typename K, typename V>
+class mrumap
+{
+private:
+    struct key_extractor {
+        typedef K result_type;
+        const result_type& operator()(const std::pair<K, V>& e) const { return e.first; }
+        result_type& operator()(std::pair<K, V>* e) const { return e->first; }
+    };
+
+    typedef boost::multi_index_container<
+        std::pair<K, V>,
+        boost::multi_index::indexed_by<
+            boost::multi_index::sequenced<>,
+            boost::multi_index::ordered_unique<key_extractor>
+        >
+    > map_type;
+
+public:
+    typedef K key_type;
+    typedef std::pair<K, V> value_type;
+    typedef typename map_type::iterator iterator;
+    typedef typename map_type::const_iterator const_iterator;
+    typedef typename map_type::size_type size_type;
+
+protected:
+    map_type m_;
+    size_type max_size_;
+
+public:
+    mrumap(size_type max_size_in = 1) { clear(max_size_in); }
+    iterator begin() { return m_.begin(); }
+    iterator end() { return m_.end(); }
+    const_iterator begin() const { return m_.begin(); }
+    const_iterator end() const { return m_.end(); }
+    size_type size() const { return m_.size(); }
+    bool empty() const { return m_.empty(); }
+    iterator find(const key_type& key) { return m_.template project<0>(boost::get<1>(m_).find(key)); }
+    const_iterator find(const key_type& key) const { return m_.template project<0>(boost::get<1>(m_).find(key)); }
+    size_type count(const key_type& key) const { return boost::get<1>(m_).count(key); }
+    void clear(size_type max_size_in) { m_.clear(); max_size_ = max_size_in; }
+    std::pair<iterator, bool> insert(const K& key, const V& value) 
+    {
+        std::pair<K, V> elem(key, value);
+        std::pair<iterator, bool> p = m_.push_front(elem);
+        if (p.second && m_.size() > max_size_) {
+            m_.pop_back();
+        }
+        return p;
+    }
+    void erase(iterator it) { m_.erase(it); }
+    void erase(const key_type& k) { boost::get<1>(m_).erase(k); }
+    size_type max_size() const { return max_size_; }
+};
+
 #endif // BITCOIN_MRUSET_H

src/test/mruset_tests.cpp

@@ -78,4 +78,68 @@ BOOST_AUTO_TEST_CASE(mruset_test)
     }
 }
 
+BOOST_AUTO_TEST_CASE(mrumap_test)
+{
+    // The mrumap being tested.
+    mrumap<int, char> mru(5000);
+
+    // Run the test 10 times.
+    for (int test = 0; test < 10; test++) {
+        // Reset mru.
+        mru.clear(5000);
+
+        // A deque + set to simulate the mruset.
+        std::deque<int> rep;
+        std::map<int, char> all;
+
+        // Insert 10000 random integers below 15000.
+        for (int j=0; j<10000; j++) {
+            int add = GetRandInt(15000);
+            char val = (char)GetRandInt(256);
+            mru.insert(add, val);
+
+            // Add the number to rep/all as well.
+            if (all.count(add) == 0) {
+               all.insert(std::make_pair<int, char>(add, val));
+               rep.push_back(add);
+               if (all.size() == 5001) {
+                   all.erase(rep.front());
+                   rep.pop_front();
+               }
+            }
+
+            if (GetRandInt(5) == 0) {
+                // With 20% chance: remove an item
+                int pos = GetRandInt(rep.size());
+                std::deque<int>::iterator it = rep.begin();
+                while (pos--) { it++; }
+                int delval = *it;
+                mru.erase(delval);
+                all.erase(delval);
+                rep.erase(it);
+            }
+
+            // Do a full comparison between mru and the simulated mru every 1000 and every 5001 elements.
+            if (j % 1000 == 0 || j % 5001 == 0) {
+                // Check that all elements that should be in there, are in there.
+                BOOST_FOREACH(int x, rep) {
+                    BOOST_CHECK(mru.count(x));
+                    BOOST_CHECK(mru.find(x)->second == all[x]);
+                }
+
+                // Check that all elements that are in there, should be in there.
+                for (mrumap<int, char>::iterator it = mru.begin(); it != mru.end(); it++) {
+                    BOOST_CHECK(all.count(it->first));
+                    BOOST_CHECK(all[it->first] == it->second);
+                }
+
+                for (int t = 0; t < 10; t++) {
+                    int r = GetRandInt(15000);
+                    BOOST_CHECK(all.count(r) == mru.count(r));
+                }
+            }
+        }
+    }
+}
+
 BOOST_AUTO_TEST_SUITE_END()