changed so each LDB key was in its own DB

src/claimtrie.cpp

@@ -127,22 +127,45 @@ void CClaimTrieData::reorderClaims(const supportEntryType& supports)
 CClaimTrie::CClaimTrie(bool fMemory, bool fWipe, int proportionalDelayFactor)
 {
     nProportionalDelayFactor = proportionalDelayFactor;
-    db.reset(new CDBWrapper(GetDataDir() / "claimtrie", 200 * 1024 * 1024, fMemory, fWipe, false));
+    if (fWipe) {
+        fs::remove_all(GetDataDir() / "claimtrie"); // old folder
+    }
+    db_TRIE_NODE_BY_HASH.reset(new CDBWrapper(GetDataDir() / "claimtrie_TRIE_NODE_BY_HASH", 240 * 1024 * 1024, fMemory, fWipe, false));
+    db_TRIE_NODE_BY_NAME.reset(new CDBWrapper(GetDataDir() / "claimtrie_TRIE_NODE_BY_NAME", 120 * 1024 * 1024, fMemory, fWipe, false));
+    db_CLAIM_BY_ID.reset(new CDBWrapper(GetDataDir() / "claimtrie_CLAIM_BY_ID", 20 * 1024 * 1024, fMemory, fWipe, false));
+    db_CLAIM_EXP_QUEUE_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_CLAIM_EXP_QUEUE_ROW", 16 * 1024 * 1024, fMemory, fWipe, false));
+    db_CLAIM_QUEUE_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_CLAIM_QUEUE_ROW", 16 * 1024 * 1024, fMemory, fWipe, false));
+    db_CLAIM_QUEUE_NAME_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_CLAIM_QUEUE_NAME_ROW", 32 * 1024 * 1024, fMemory, fWipe, false));
+    db_SUPPORT_EXP_QUEUE_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_SUPPORT_EXP_QUEUE_ROW", 12 * 1024 * 1024, fMemory, fWipe, false));
+    db_SUPPORT_QUEUE_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_SUPPORT_QUEUE_ROW", 12 * 1024 * 1024, fMemory, fWipe, false));
+    db_SUPPORT_QUEUE_NAME_ROW.reset(new CDBWrapper(GetDataDir() / "claimtrie_SUPPORT_QUEUE_NAME_ROW", 24 * 1024 * 1024, fMemory, fWipe, false));
+    db_SUPPORT.reset(new CDBWrapper(GetDataDir() / "claimtrie_SUPPORT", 24 * 1024 * 1024, fMemory, fWipe, false));
 }
 
 bool CClaimTrie::SyncToDisk()
 {
-    return db && db->Sync();
+    auto success = true;
+    success &= db_TRIE_NODE_BY_HASH->Sync();
+    success &= db_TRIE_NODE_BY_NAME->Sync();
+    success &= db_CLAIM_BY_ID->Sync();
+    success &= db_CLAIM_EXP_QUEUE_ROW->Sync();
+    success &= db_CLAIM_QUEUE_ROW->Sync();
+    success &= db_CLAIM_QUEUE_NAME_ROW->Sync();
+    success &= db_SUPPORT_EXP_QUEUE_ROW->Sync();
+    success &= db_SUPPORT_QUEUE_ROW->Sync();
+    success &= db_SUPPORT_QUEUE_NAME_ROW->Sync();
+    success &= db_SUPPORT->Sync();
+    return success;
 }
 
 template <typename Key, typename Container>
-typename Container::value_type* getQueue(CDBWrapper& db, uint8_t dbkey, const Key& key, Container& queue, bool create)
+typename Container::value_type* getQueue(CDBWrapper& db, const Key& key, Container& queue, bool create)
 {
     auto itQueue = queue.find(key);
     if (itQueue != queue.end())
         return &(*itQueue);
     typename Container::mapped_type row;
-    if (db.Read(std::make_pair(dbkey, key), row) || create) {
+    if (db.Read(key, row) || create) {
         auto ret = queue.insert(std::make_pair(key, row));
         assert(ret.second);
         return &(*ret.first);
@@ -160,13 +183,13 @@ inline constexpr bool supportedType()
 template <>
 std::pair<const int, std::vector<queueEntryType<CClaimValue>>>* CClaimTrieCacheBase::getQueueCacheRow(int nHeight, bool createIfNotExists)
 {
-    return getQueue(*(base->db), CLAIM_QUEUE_ROW, nHeight, claimQueueCache, createIfNotExists);
+    return getQueue(*(base->db_CLAIM_QUEUE_ROW), nHeight, claimQueueCache, createIfNotExists);
 }
 
 template <>
 std::pair<const int, std::vector<queueEntryType<CSupportValue>>>* CClaimTrieCacheBase::getQueueCacheRow(int nHeight, bool createIfNotExists)
 {
-    return getQueue(*(base->db), SUPPORT_QUEUE_ROW, nHeight, supportQueueCache, createIfNotExists);
+    return getQueue(*(base->db_SUPPORT_QUEUE_ROW), nHeight, supportQueueCache, createIfNotExists);
 }
 
 template <typename T>
@@ -179,13 +202,13 @@ std::pair<const int, std::vector<queueEntryType<T>>>* CClaimTrieCacheBase::getQu
 template <>
 typename queueNameType::value_type* CClaimTrieCacheBase::getQueueCacheNameRow<CClaimValue>(const std::string& name, bool createIfNotExists)
 {
-    return getQueue(*(base->db), CLAIM_QUEUE_NAME_ROW, name, claimQueueNameCache, createIfNotExists);
+    return getQueue(*(base->db_CLAIM_QUEUE_NAME_ROW), name, claimQueueNameCache, createIfNotExists);
 }
 
 template <>
 typename queueNameType::value_type* CClaimTrieCacheBase::getQueueCacheNameRow<CSupportValue>(const std::string& name, bool createIfNotExists)
 {
-    return getQueue(*(base->db), SUPPORT_QUEUE_NAME_ROW, name, supportQueueNameCache, createIfNotExists);
+    return getQueue(*(base->db_SUPPORT_QUEUE_NAME_ROW), name, supportQueueNameCache, createIfNotExists);
 }
 
 template <typename T>
@@ -198,13 +221,13 @@ typename queueNameType::value_type* CClaimTrieCacheBase::getQueueCacheNameRow(co
 template <>
 typename expirationQueueType::value_type* CClaimTrieCacheBase::getExpirationQueueCacheRow<CClaimValue>(int nHeight, bool createIfNotExists)
 {
-    return getQueue(*(base->db), CLAIM_EXP_QUEUE_ROW, nHeight, expirationQueueCache, createIfNotExists);
+    return getQueue(*(base->db_CLAIM_EXP_QUEUE_ROW), nHeight, expirationQueueCache, createIfNotExists);
 }
 
 template <>
 typename expirationQueueType::value_type* CClaimTrieCacheBase::getExpirationQueueCacheRow<CSupportValue>(int nHeight, bool createIfNotExists)
 {
-    return getQueue(*(base->db), SUPPORT_EXP_QUEUE_ROW, nHeight, supportExpirationQueueCache, createIfNotExists);
+    return getQueue(*(base->db_SUPPORT_EXP_QUEUE_ROW), nHeight, supportExpirationQueueCache, createIfNotExists);
 }
 
 template <typename T>
@@ -239,7 +262,7 @@ supportEntryType CClaimTrieCacheBase::getSupportsForName(const std::string& name
         return sit->second;
 
     supportEntryType supports;
-    if (base->db->Read(std::make_pair(SUPPORT, name), supports)) // don't trust the try/catch in here
+    if (base->db_SUPPORT->Read(name, supports)) // don't trust the try/catch in here
         return supports;
     return {};
 }
@@ -489,7 +512,7 @@ std::vector<std::pair<std::string, CClaimTrieDataNode>> CClaimTrie::nodes(const
 }
 
 bool CClaimTrie::contains(const std::string &key) const {
-    return db->Exists(std::make_pair(TRIE_NODE_BY_NAME, key));
+    return db_TRIE_NODE_BY_NAME->Exists(key);
 }
 
 bool CClaimTrie::empty() const {
@@ -498,20 +521,20 @@ bool CClaimTrie::empty() const {
 
 bool CClaimTrie::find(const std::string &key, CClaimTrieDataNode &node) const {
     uint256 hash;
-    if (!db->Read(std::make_pair(TRIE_NODE_BY_NAME, key), hash))
+    if (!db_TRIE_NODE_BY_NAME->Read(key, hash))
         return false;
     auto found = find(hash, node);
     return found;
 }
 
 bool CClaimTrie::find(const uint256 &key, CClaimTrieDataNode &node) const {
-    return db->Read(std::make_pair(TRIE_NODE_BY_HASH, key), node);
+    return db_TRIE_NODE_BY_HASH->Read(key, node);
 }
 
 bool CClaimTrieCacheBase::getClaimById(const uint160& claimId, std::string& name, CClaimValue& claim) const
 {
     CClaimIndexElement element;
-    if (!base->db->Read(std::make_pair(CLAIM_BY_ID, claimId), element))
+    if (!base->db_CLAIM_BY_ID->Read(claimId, element))
         return false;
     if (element.claim.claimId == claimId) {
         name = element.name;
@@ -522,25 +545,27 @@ bool CClaimTrieCacheBase::getClaimById(const uint160& claimId, std::string& name
 }
 
 template <typename K, typename T>
-void BatchWrite(CDBBatch& batch, uint8_t dbkey, const K& key, const std::vector<T>& value)
+void BatchWrite(CDBBatch& batch, const K& key, const std::vector<T>& value)
 {
     if (value.empty()) {
-        batch.Erase(std::make_pair(dbkey, key));
+        batch.Erase(key);
     } else {
-        batch.Write(std::make_pair(dbkey, key), value);
+        batch.Write(key, value);
     }
 }
 
 template <typename Container>
-void BatchWriteQueue(CDBBatch& batch, uint8_t dbkey, const Container& queue)
+bool BatchWriteQueue(CDBWrapper& db, const Container& queue)
 {
+    CDBBatch batch(db);
     for (auto& itQueue : queue)
-        BatchWrite(batch, dbkey, itQueue.first, itQueue.second);
+        BatchWrite(batch, itQueue.first, itQueue.second);
+    return db.WriteBatch(batch);
 }
 
 bool CClaimTrieCacheBase::flush()
 {
-    CDBBatch batch(*(base->db));
+    CDBBatch batch_CLAIM_BY_ID(*(base->db_CLAIM_BY_ID));
 
     for (const auto& claim : claimsToDeleteFromByIdIndex) {
         auto it = std::find_if(claimsToAddToByIdIndex.begin(), claimsToAddToByIdIndex.end(),
@@ -549,11 +574,13 @@ bool CClaimTrieCacheBase::flush()
             }
         );
         if (it == claimsToAddToByIdIndex.end())
-            batch.Erase(std::make_pair(CLAIM_BY_ID, claim.claimId));
+            batch_CLAIM_BY_ID.Erase(claim.claimId);
     }
 
     for (const auto& e : claimsToAddToByIdIndex)
-        batch.Write(std::make_pair(CLAIM_BY_ID, e.claim.claimId), e);
+        batch_CLAIM_BY_ID.Write(e.claim.claimId, e);
+
+    auto success = base->db_CLAIM_BY_ID->WriteBatch(batch_CLAIM_BY_ID);
 
     getMerkleHash();
 
@@ -566,6 +593,8 @@ bool CClaimTrieCacheBase::flush()
             forDeletion.insert(node.first);
     }
 
+    CDBBatch batch_TRIE_NODE_BY_HASH(*(base->db_TRIE_NODE_BY_HASH));
+    CDBBatch batch_TRIE_NODE_BY_NAME(*(base->db_TRIE_NODE_BY_NAME));
     for (auto it = nodesToAddOrUpdate.begin(); it != nodesToAddOrUpdate.end(); ++it) {
         forDeletion.erase(it.key());
         if (!dirtyNodes.count(it.key()))
@@ -576,32 +605,35 @@ bool CClaimTrieCacheBase::flush()
         for (auto &child: it.children()) // ordering here is important
             node.children.emplace_back(child.key().substr(it.key().size()), child->hash);
 
-        batch.Write(std::make_pair(TRIE_NODE_BY_HASH, it->hash), node);
+        batch_TRIE_NODE_BY_HASH.Write(it->hash, node);
-        batch.Write(std::make_pair(TRIE_NODE_BY_NAME, it.key()), it->hash);
+        batch_TRIE_NODE_BY_NAME.Write(it.key(), it->hash);
     }
 
+    success &= base->db_TRIE_NODE_BY_HASH->WriteBatch(batch_TRIE_NODE_BY_HASH);
+
     for (auto& name: forDeletion) {
-        batch.Erase(std::make_pair(TRIE_NODE_BY_NAME, name));
+        batch_TRIE_NODE_BY_NAME.Erase(name);
     }
 
-    BatchWriteQueue(batch, SUPPORT, supportCache);
+    success &= base->db_TRIE_NODE_BY_NAME->WriteBatch(batch_TRIE_NODE_BY_NAME);
 
-    BatchWriteQueue(batch, CLAIM_QUEUE_ROW, claimQueueCache);
+    success &= BatchWriteQueue(*(base->db_SUPPORT), supportCache);
-    BatchWriteQueue(batch, CLAIM_QUEUE_NAME_ROW, claimQueueNameCache);
-    BatchWriteQueue(batch, CLAIM_EXP_QUEUE_ROW, expirationQueueCache);
 
-    BatchWriteQueue(batch, SUPPORT_QUEUE_ROW, supportQueueCache);
+    success &= BatchWriteQueue(*(base->db_CLAIM_QUEUE_ROW), claimQueueCache);
-    BatchWriteQueue(batch, SUPPORT_QUEUE_NAME_ROW, supportQueueNameCache);
+    success &= BatchWriteQueue(*(base->db_CLAIM_QUEUE_NAME_ROW), claimQueueNameCache);
-    BatchWriteQueue(batch, SUPPORT_EXP_QUEUE_ROW, supportExpirationQueueCache);
+    success &= BatchWriteQueue(*(base->db_CLAIM_EXP_QUEUE_ROW), expirationQueueCache);
+
+    success &= BatchWriteQueue(*(base->db_SUPPORT_QUEUE_ROW), supportQueueCache);
+    success &= BatchWriteQueue(*(base->db_SUPPORT_QUEUE_NAME_ROW), supportQueueNameCache);
+    success &= BatchWriteQueue(*(base->db_SUPPORT_EXP_QUEUE_ROW), supportExpirationQueueCache);
 
     base->nNextHeight = nNextHeight;
     if (!nodesToAddOrUpdate.empty() && (LogAcceptCategory(BCLog::CLAIMS) || LogAcceptCategory(BCLog::BENCH))) {
-        LogPrintf("TrieCache size: %zu nodes on block %d, batch writes %zu bytes.\n",
+        LogPrintf("TrieCache size: %zu nodes on block %d.\n",
-                nodesToAddOrUpdate.height(), nNextHeight, batch.SizeEstimate());
+                nodesToAddOrUpdate.height(), nNextHeight);
     }
-    auto ret = base->db->WriteBatch(batch);
     clear();
-    return ret;
+    return success;
 }
 
 bool CClaimTrieCacheBase::validateTrieConsistency(const CBlockIndex* tip)
@@ -623,7 +655,7 @@ bool CClaimTrieCacheBase::ReadFromDisk(const CBlockIndex* tip)
     base->nNextHeight = nNextHeight = tip ? tip->nHeight + 1 : 0;
     clear();
 
-    if (tip && (base->db->Exists(std::make_pair(TRIE_NODE, std::string())) || !base->db->Exists(std::make_pair(TRIE_NODE_BY_HASH, tip->hashClaimTrie)))) {
+    if (tip && fs::is_directory(GetDataDir() / "claimtrie")) {
         LogPrintf("The claim trie database contains deprecated data and will need to be rebuilt");
         return false;
     }

src/claimtrie.h

@@ -17,19 +17,6 @@
 #include <unordered_map>
 #include <unordered_set>
 
-// leveldb keys
-#define TRIE_NODE 'n' // deprecated
-#define TRIE_NODE_BY_HASH 'h'
-#define TRIE_NODE_BY_NAME 'g'
-#define CLAIM_BY_ID 'i'
-#define CLAIM_QUEUE_ROW 'r'
-#define CLAIM_QUEUE_NAME_ROW 'm'
-#define CLAIM_EXP_QUEUE_ROW 'e'
-#define SUPPORT 's'
-#define SUPPORT_QUEUE_ROW 'u'
-#define SUPPORT_QUEUE_NAME_ROW 'p'
-#define SUPPORT_EXP_QUEUE_ROW 'x'
-
 uint256 getValueHash(const COutPoint& outPoint, int nHeightOfLastTakeover);
 
 struct CClaimValue
@@ -321,7 +308,16 @@ class CClaimTrie
 {
     int nNextHeight = 0;
     int nProportionalDelayFactor = 0;
-    std::unique_ptr<CDBWrapper> db;
+    std::unique_ptr<CDBWrapper> db_TRIE_NODE_BY_HASH;
+    std::unique_ptr<CDBWrapper> db_TRIE_NODE_BY_NAME;
+    std::unique_ptr<CDBWrapper> db_CLAIM_BY_ID;
+    std::unique_ptr<CDBWrapper> db_CLAIM_EXP_QUEUE_ROW;
+    std::unique_ptr<CDBWrapper> db_CLAIM_QUEUE_ROW;
+    std::unique_ptr<CDBWrapper> db_CLAIM_QUEUE_NAME_ROW;
+    std::unique_ptr<CDBWrapper> db_SUPPORT_EXP_QUEUE_ROW;
+    std::unique_ptr<CDBWrapper> db_SUPPORT_QUEUE_ROW;
+    std::unique_ptr<CDBWrapper> db_SUPPORT_QUEUE_NAME_ROW;
+    std::unique_ptr<CDBWrapper> db_SUPPORT;
 
 public:
     CClaimTrie() = default;

src/claimtrieforks.cpp

@@ -61,29 +61,31 @@ bool CClaimTrieCacheExpirationFork::forkForExpirationChange(bool increment)
     */
 
     //look through db for expiration queues, if we haven't already found it in dirty expiration queue
-    boost::scoped_ptr<CDBIterator> pcursor(base->db->NewIterator());
+    boost::scoped_ptr<CDBIterator> pcursor_ceqr(base->db_CLAIM_EXP_QUEUE_ROW->NewIterator());
-    for (pcursor->SeekToFirst(); pcursor->Valid(); pcursor->Next()) {
+    for (pcursor_ceqr->SeekToFirst(); pcursor_ceqr->Valid(); pcursor_ceqr->Next()) {
-        std::pair<uint8_t, int> key;
+        int height;
-        if (!pcursor->GetKey(key))
+        if (!pcursor_ceqr->GetKey(height))
             continue;
-        int height = key.second;
-        if (key.first == CLAIM_EXP_QUEUE_ROW) {
         expirationQueueRowType row;
-            if (pcursor->GetValue(row)) {
+        if (pcursor_ceqr->GetValue(row)) {
             reactivateClaim(row, height, increment);
         } else {
             return error("%s(): error reading expiration queue rows from disk", __func__);
         }
-        } else if (key.first == SUPPORT_EXP_QUEUE_ROW) {
+    }
+
+    boost::scoped_ptr<CDBIterator> pcursor_seqr(base->db_SUPPORT_EXP_QUEUE_ROW->NewIterator());
+    for (pcursor_seqr->SeekToFirst(); pcursor_seqr->Valid(); pcursor_seqr->Next()) {
+        int height;
+        if (!pcursor_seqr->GetKey(height))
+            continue;
         expirationQueueRowType row;
-            if (pcursor->GetValue(row)) {
+        if (pcursor_seqr->GetValue(row)) {
             reactivateSupport(row, height, increment);
         } else {
             return error("%s(): error reading support expiration queue rows from disk", __func__);
         }
     }
-    }
-
     return true;
 }
 
@@ -161,15 +163,14 @@ bool CClaimTrieCacheNormalizationFork::normalizeAllNamesInTrieIfNecessary(insert
     // run the one-time upgrade of all names that need to change
     // it modifies the (cache) trie as it goes, so we need to grab everything to be modified first
 
-    boost::scoped_ptr<CDBIterator> pcursor(base->db->NewIterator());
+    boost::scoped_ptr<CDBIterator> pcursor(base->db_TRIE_NODE_BY_NAME->NewIterator());
     for (pcursor->SeekToFirst(); pcursor->Valid(); pcursor->Next()) {
-        std::pair<uint8_t, std::string> key;
+        std::string name;
-        if (!pcursor->GetKey(key) || key.first != TRIE_NODE_BY_NAME)
+        if (!pcursor->GetKey(name))
             continue;
 
-        const auto& name = key.second;
         const std::string normalized = normalizeClaimName(name, true);
-        if (normalized == key.second)
+        if (normalized == name)
             continue;
 
         auto supports = getSupportsForName(name);

src/dbwrapper.cpp

@@ -116,7 +116,7 @@ static leveldb::Options GetOptions(size_t nCacheSize)
 }
 
 CDBWrapper::CDBWrapper(const fs::path& path, size_t nCacheSize, bool fMemory, bool fWipe, bool obfuscate)
-    : m_name(fs::basename(path))
+    : m_name(fs::basename(path)), ssKey(SER_DISK, CLIENT_VERSION), ssValue(SER_DISK, CLIENT_VERSION)
 {
     penv = nullptr;
     readoptions.verify_checksums = true;
@@ -239,6 +239,11 @@ bool CDBIterator::Valid() const { return piter->Valid(); }
 void CDBIterator::SeekToFirst() { piter->SeekToFirst(); }
 void CDBIterator::Next() { piter->Next(); }
 
+bool CDBWrapper::Sync() {
+    CDBBatch batch(*this);
+    return WriteBatch(batch, true);
+}
+
 namespace dbwrapper_private {
 
 void HandleError(const leveldb::Status& status)

src/dbwrapper.h

@@ -16,9 +16,6 @@
 #include <leveldb/db.h>
 #include <leveldb/write_batch.h>
 
-static const size_t DBWRAPPER_PREALLOC_KEY_SIZE = 64;
-static const size_t DBWRAPPER_PREALLOC_VALUE_SIZE = 1024;
-
 class dbwrapper_error : public std::runtime_error
 {
 public:
@@ -43,77 +40,6 @@ const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w);
 
 };
 
-/** Batch of changes queued to be written to a CDBWrapper */
-class CDBBatch
-{
-    friend class CDBWrapper;
-
-private:
-    const CDBWrapper &parent;
-    leveldb::WriteBatch batch;
-
-    CDataStream ssKey;
-    CDataStream ssValue;
-
-    size_t size_estimate;
-
-public:
-    /**
-     * @param[in] _parent   CDBWrapper that this batch is to be submitted to
-     */
-    explicit CDBBatch(const CDBWrapper &_parent) : parent(_parent), ssKey(SER_DISK, CLIENT_VERSION), ssValue(SER_DISK, CLIENT_VERSION), size_estimate(0) { };
-
-    void Clear()
-    {
-        batch.Clear();
-        size_estimate = 0;
-    }
-
-    template <typename K, typename V>
-    void Write(const K& key, const V& value)
-    {
-        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
-        ssKey << key;
-        leveldb::Slice slKey(ssKey.data(), ssKey.size());
-
-        ssValue.reserve(DBWRAPPER_PREALLOC_VALUE_SIZE);
-        ssValue << value;
-        ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
-        leveldb::Slice slValue(ssValue.data(), ssValue.size());
-
-        batch.Put(slKey, slValue);
-        // LevelDB serializes writes as:
-        // - byte: header
-        // - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
-        // - byte[]: key
-        // - varint: value length
-        // - byte[]: value
-        // The formula below assumes the key and value are both less than 16k.
-        size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
-        ssKey.clear();
-        ssValue.clear();
-    }
-
-    template <typename K>
-    void Erase(const K& key)
-    {
-        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
-        ssKey << key;
-        leveldb::Slice slKey(ssKey.data(), ssKey.size());
-
-        batch.Delete(slKey);
-        // LevelDB serializes erases as:
-        // - byte: header
-        // - varint: key length
-        // - byte[]: key
-        // The formula below assumes the key is less than 16kB.
-        size_estimate += 2 + (slKey.size() > 127) + slKey.size();
-        ssKey.clear();
-    }
-
-    size_t SizeEstimate() const { return size_estimate; }
-};
-
 class CDBIterator
 {
 private:
@@ -135,10 +61,10 @@ public:
     void SeekToFirst();
 
     template<typename K> void Seek(const K& key) {
-        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
+        CDataStream ssKey1(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
+        // ssKey1.reserve(parent.ssKey.capacity());
-        ssKey << key;
+        ssKey1 << key;
-        leveldb::Slice slKey(ssKey.data(), ssKey.size());
+        leveldb::Slice slKey(ssKey1.data(), ssKey1.size());
         piter->Seek(slKey);
     }
 
@@ -173,6 +99,8 @@ public:
 
 };
 
+class CDBBatch;
+
 class CDBWrapper
 {
     friend const std::vector<unsigned char>& dbwrapper_private::GetObfuscateKey(const CDBWrapper &w);
@@ -213,6 +141,8 @@ private:
     std::vector<unsigned char> CreateObfuscateKey() const;
 
 public:
+    mutable CDataStream ssKey, ssValue;
+
     /**
      * @param[in] path        Location in the filesystem where leveldb data will be stored.
      * @param[in] nCacheSize  Configures various leveldb cache settings.
@@ -230,13 +160,12 @@ public:
     template <typename K, typename V>
     bool Read(const K& key, V& value) const
     {
-        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(ssKey.data(), ssKey.size());
 
         std::string strValue;
         leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
+        ssKey.clear();
         if (!status.ok()) {
             if (status.IsNotFound())
                 return false;
@@ -254,23 +183,17 @@ public:
     }
 
     template <typename K, typename V>
-    bool Write(const K& key, const V& value, bool fSync = false)
+    bool Write(const K& key, const V& value, bool fSync = false);
-    {
-        CDBBatch batch(*this);
-        batch.Write(key, value);
-        return WriteBatch(batch, fSync);
-    }
 
     template <typename K>
     bool Exists(const K& key) const
     {
-        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(ssKey.data(), ssKey.size());
 
         std::string strValue;
         leveldb::Status status = pdb->Get(readoptions, slKey, &strValue);
+        ssKey.clear();
         if (!status.ok()) {
             if (status.IsNotFound())
                 return false;
@@ -281,12 +204,7 @@ public:
     }
 
     template <typename K>
-    bool Erase(const K& key, bool fSync = false)
+    bool Erase(const K& key, bool fSync = false);
-    {
-        CDBBatch batch(*this);
-        batch.Erase(key);
-        return WriteBatch(batch, fSync);
-    }
 
     bool WriteBatch(CDBBatch& batch, bool fSync = false);
 
@@ -299,11 +217,7 @@ public:
         return true;
     }
 
-    bool Sync()
+    bool Sync();
-    {
-        CDBBatch batch(*this);
-        return WriteBatch(batch, true);
-    }
 
     CDBIterator *NewIterator()
     {
@@ -319,8 +233,6 @@ public:
     size_t EstimateSize(const K& key_begin, const K& key_end) const
     {
         CDataStream ssKey1(SER_DISK, CLIENT_VERSION), ssKey2(SER_DISK, CLIENT_VERSION);
-        ssKey1.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
-        ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey1 << key_begin;
         ssKey2 << key_end;
         leveldb::Slice slKey1(ssKey1.data(), ssKey1.size());
@@ -338,8 +250,8 @@ public:
     void CompactRange(const K& key_begin, const K& key_end) const
     {
         CDataStream ssKey1(SER_DISK, CLIENT_VERSION), ssKey2(SER_DISK, CLIENT_VERSION);
-        ssKey1.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
+        ssKey1.reserve(ssKey.capacity());
-        ssKey2.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
+        ssKey2.reserve(ssKey.capacity());
         ssKey1 << key_begin;
         ssKey2 << key_end;
         leveldb::Slice slKey1(ssKey1.data(), ssKey1.size());
@@ -349,4 +261,83 @@ public:
 
 };
 
+/** Batch of changes queued to be written to a CDBWrapper */
+class CDBBatch
+{
+    friend class CDBWrapper;
+    const CDBWrapper &parent;
+    leveldb::WriteBatch batch;
+
+    size_t size_estimate;
+
+public:
+    /**
+     * @param[in] _parent   CDBWrapper that this batch is to be submitted to
+     */
+    explicit CDBBatch(const CDBWrapper &_parent) : parent(_parent), size_estimate(0) { };
+
+    void Clear()
+    {
+        batch.Clear();
+        size_estimate = 0;
+    }
+
+    template <typename K, typename V>
+    void Write(const K& key, const V& value)
+    {
+        assert(parent.ssKey.empty());
+        parent.ssKey << key;
+        leveldb::Slice slKey(parent.ssKey.data(), parent.ssKey.size());
+
+        assert(parent.ssValue.empty());
+        parent.ssValue << value;
+        parent.ssValue.Xor(dbwrapper_private::GetObfuscateKey(parent));
+        leveldb::Slice slValue(parent.ssValue.data(), parent.ssValue.size());
+
+        batch.Put(slKey, slValue);
+        // LevelDB serializes writes as:
+        // - byte: header
+        // - varint: key length (1 byte up to 127B, 2 bytes up to 16383B, ...)
+        // - byte[]: key
+        // - varint: value length
+        // - byte[]: value
+        // The formula below assumes the key and value are both less than 16k.
+        size_estimate += 3 + (slKey.size() > 127) + slKey.size() + (slValue.size() > 127) + slValue.size();
+        parent.ssKey.clear();
+        parent.ssValue.clear();
+    }
+
+    template <typename K>
+    void Erase(const K& key)
+    {
+        parent.ssKey << key;
+        leveldb::Slice slKey(parent.ssKey.data(), parent.ssKey.size());
+
+        batch.Delete(slKey);
+        // LevelDB serializes erases as:
+        // - byte: header
+        // - varint: key length
+        // - byte[]: key
+        // The formula below assumes the key is less than 16kB.
+        size_estimate += 2 + (slKey.size() > 127) + slKey.size();
+        parent.ssKey.clear();
+    }
+
+    size_t SizeEstimate() const { return size_estimate; }
+};
+
+template<typename K>
+bool CDBWrapper::Erase(const K &key, bool fSync) {
+    CDBBatch batch(*this);
+    batch.Erase(key);
+    return WriteBatch(batch, fSync);
+}
+
+template<typename K, typename V>
+bool CDBWrapper::Write(const K &key, const V &value, bool fSync) {
+    CDBBatch batch(*this);
+    batch.Write(key, value);
+    return WriteBatch(batch, fSync);
+}
+
 #endif // BITCOIN_DBWRAPPER_H

src/streams.h

@@ -227,6 +227,11 @@ public:
         return (std::string(begin(), end()));
     }
 
+    std::size_t capacity() const
+    {
+        return vch.capacity();
+    }
+
 
     //
     // Vector subset

src/test/claimtriebranching_tests.cpp

@@ -319,30 +319,13 @@ struct ClaimTrieChainFixture: public CClaimTrieCacheExpirationFork
         DecrementBlocks(chainActive.Height() - mark);
     }
 
-    template <typename K>
-    bool keyTypeEmpty(uint8_t keyType)
-    {
-        boost::scoped_ptr<CDBIterator> pcursor(base->db->NewIterator());
-        pcursor->SeekToFirst();
-
-        while (pcursor->Valid()) {
-            std::pair<uint8_t, K> key;
-            if (pcursor->GetKey(key)) {
-                if (key.first == keyType)
-                    return false;
-            }
-            pcursor->Next();
-        }
-        return true;
-    }
-
     bool queueEmpty()
     {
         for (const auto& claimQueue: claimQueueCache) {
             if (!claimQueue.second.empty())
                 return false;
         }
-        return keyTypeEmpty<int>(CLAIM_QUEUE_ROW);
+        return base->db_CLAIM_QUEUE_ROW->IsEmpty();
     }
 
     bool expirationQueueEmpty()
@@ -351,7 +334,7 @@ struct ClaimTrieChainFixture: public CClaimTrieCacheExpirationFork
             if (!expirationQueue.second.empty())
                 return false;
         }
-        return keyTypeEmpty<int>(CLAIM_EXP_QUEUE_ROW);
+        return base->db_CLAIM_EXP_QUEUE_ROW->IsEmpty();
     }
 
     bool supportEmpty()
@@ -360,7 +343,7 @@ struct ClaimTrieChainFixture: public CClaimTrieCacheExpirationFork
             if (!entry.second.empty())
                 return false;
         }
-        return supportCache.empty() && keyTypeEmpty<std::string>(SUPPORT);
+        return supportCache.empty() && base->db_SUPPORT->IsEmpty();
     }
 
     bool supportQueueEmpty()
@@ -369,7 +352,7 @@ struct ClaimTrieChainFixture: public CClaimTrieCacheExpirationFork
             if (!support.second.empty())
                 return false;
         }
-        return keyTypeEmpty<int>(SUPPORT_QUEUE_ROW);
+        return base->db_SUPPORT_QUEUE_ROW->IsEmpty();
     }
 
     int proportionalDelayFactor()