Small OnPersist optimization (#1058)

* Small update

* Cache native persist script

neo/Ledger/Blockchain.cs

@@ -53,6 +53,7 @@ public class FillCompleted { }
  Transactions = new[] { DeployNativeContracts() }
  };
 
+ private readonly static byte[] onPersistNativeContractScript;
  private const int MaxTxToReverifyPerIdle = 10;
  private static readonly object lockObj = new object();
  private readonly NeoSystem system;
@@ -83,6 +84,15 @@ public static Blockchain Singleton
  static Blockchain()
  {
  GenesisBlock.RebuildMerkleRoot();
+
+ NativeContract[] contracts = { NativeContract.GAS, NativeContract.NEO };
+ using (ScriptBuilder sb = new ScriptBuilder())
+ {
+ foreach (NativeContract contract in contracts)
+ sb.EmitAppCall(contract.Hash, "onPersist");
+
+ onPersistNativeContractScript = sb.ToArray();
+ }
  }
 
  public Blockchain(NeoSystem system, Store store)
@@ -416,15 +426,9 @@ private void Persist(Block block)
  snapshot.PersistingBlock = block;
  if (block.Index > 0)
  {
- NativeContract[] contracts = { NativeContract.GAS, NativeContract.NEO };
  using (ApplicationEngine engine = new ApplicationEngine(TriggerType.System, null, snapshot, 0, true))
  {
- using (ScriptBuilder sb = new ScriptBuilder())
- {
- foreach (NativeContract contract in contracts)
- sb.EmitAppCall(contract.Hash, "onPersist");
- engine.LoadScript(sb.ToArray());
- }
+ engine.LoadScript(onPersistNativeContractScript);
  if (engine.Execute() != VMState.HALT) throw new InvalidOperationException();
  ApplicationExecuted application_executed = new ApplicationExecuted(engine);
  Context.System.EventStream.Publish(application_executed);
@@ -455,13 +459,11 @@ private void Persist(Block block)
  all_application_executed.Add(application_executed);
  }
  }
- snapshot.BlockHashIndex.GetAndChange().Hash = block.Hash;
- snapshot.BlockHashIndex.GetAndChange().Index = block.Index;
+ snapshot.BlockHashIndex.GetAndChange().Set(block);
  if (block.Index == header_index.Count)
  {
  header_index.Add(block.Hash);
- snapshot.HeaderHashIndex.GetAndChange().Hash = block.Hash;
- snapshot.HeaderHashIndex.GetAndChange().Index = block.Index;
+ snapshot.HeaderHashIndex.GetAndChange().Set(block);
  }
  foreach (IPersistencePlugin plugin in Plugin.PersistencePlugins)
  plugin.OnPersist(snapshot, all_application_executed);

neo/Ledger/HashIndexState.cs

@@ -1,4 +1,5 @@
 using Neo.IO;
+using Neo.Network.P2P.Payloads;
 using System.IO;
 
 namespace Neo.Ledger
@@ -36,5 +37,11 @@ void ISerializable.Serialize(BinaryWriter writer)
  writer.Write(Hash);
  writer.Write(Index);
  }
+
+ internal void Set(BlockBase block)
+ {
+ Hash = block.Hash;
+ Index = block.Index;
+ }
  }
 }