Merge pull request #282 from dagurval/18-12-batchbatches

Batch construct batches
bitcoinxt · Dec 31, 2017 · 505e665 · 505e665
2 parents 79a378f + ce990fa
commit 505e665
Showing 1 changed file with 17 additions and 9 deletions.
diff --git a/src/dbwrapper.h b/src/dbwrapper.h
@@ -16,6 +16,9 @@
 #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:
@@ -40,32 +43,37 @@ class CDBBatch
 private:
     leveldb::WriteBatch batch;
 
+    CDataStream ssKey;
+    CDataStream ssValue;
+
 public:
+    CDBBatch() : ssKey(SER_DISK, CLIENT_VERSION), ssValue(SER_DISK, CLIENT_VERSION) { };
+
     template <typename K, typename V>
     void Write(const K& key, const V& value)
     {
-        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(ssKey.GetSerializeSize(key));
+        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(&ssKey[0], ssKey.size());
 
-        CDataStream ssValue(SER_DISK, CLIENT_VERSION);
-        ssValue.reserve(ssValue.GetSerializeSize(value));
+        ssValue.reserve(DBWRAPPER_PREALLOC_VALUE_SIZE);
         ssValue << value;
         leveldb::Slice slValue(&ssValue[0], ssValue.size());
 
         batch.Put(slKey, slValue);
+        ssKey.clear();
+        ssValue.clear();
     }
 
     template <typename K>
     void Erase(const K& key)
     {
-        CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(ssKey.GetSerializeSize(key));
+        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(&ssKey[0], ssKey.size());
 
         batch.Delete(slKey);
+        ssKey.clear();
     }
 };
 
@@ -84,7 +92,7 @@ class CDBIterator
 
     template<typename K> void Seek(const K& key) {
         CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(ssKey.GetSerializeSize(key));
+        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(&ssKey[0], ssKey.size());
         piter->Seek(slKey);
@@ -161,7 +169,7 @@ class CDBWrapper
     bool Read(const K& key, V& value) const
     {
         CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(ssKey.GetSerializeSize(key));
+        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(&ssKey[0], ssKey.size());
 
@@ -194,7 +202,7 @@ class CDBWrapper
     bool Exists(const K& key) const
     {
         CDataStream ssKey(SER_DISK, CLIENT_VERSION);
-        ssKey.reserve(ssKey.GetSerializeSize(key));
+        ssKey.reserve(DBWRAPPER_PREALLOC_KEY_SIZE);
         ssKey << key;
         leveldb::Slice slKey(&ssKey[0], ssKey.size());