Merge pull request #134 from rsksmart/fix_merge_mining_with_cache

Fix merge mining with cache for ginger
rsksmart · Jul 10, 2017 · 1818932 · 1818932
2 parents 5e93590 + 7ef1e22
commit 1818932
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Showing 3 changed files with 58 additions and 5 deletions.
diff --git a/rskj-core/src/main/java/co/rsk/mine/MinerClientImpl.java b/rskj-core/src/main/java/co/rsk/mine/MinerClientImpl.java
@@ -42,6 +42,7 @@
 
 @Component("MinerClient")
 public class MinerClientImpl implements MinerClient {
+    private long nextNonceToUse = 0;
 
     @Autowired
     private Rsk rsk;
@@ -171,14 +172,16 @@ public boolean mineBlock() {
      */
     private boolean findNonce(@Nonnull final co.rsk.bitcoinj.core.BtcBlock bitcoinMergedMiningBlock,
                               @Nonnull final BigInteger target) {
+        bitcoinMergedMiningBlock.setNonce(nextNonceToUse++);
+
         while (!stop && !newBestBlockArrivedFromAnotherNode) {
             // Is our proof of work valid yet?
             BigInteger blockHashBI = bitcoinMergedMiningBlock.getHash().toBigInteger();
             if (blockHashBI.compareTo(target) <= 0) {
                 return true;
             }
             // No, so increment the nonce and try again.
-            bitcoinMergedMiningBlock.setNonce(bitcoinMergedMiningBlock.getNonce() + 1);
+            bitcoinMergedMiningBlock.setNonce(nextNonceToUse++);
             if (bitcoinMergedMiningBlock.getNonce() % 100000 == 0) {
                 logger.debug("Solving block. Nonce: " + bitcoinMergedMiningBlock.getNonce());
             }

diff --git a/rskj-core/src/main/java/co/rsk/mine/MinerServerImpl.java b/rskj-core/src/main/java/co/rsk/mine/MinerServerImpl.java
@@ -151,20 +151,26 @@ public void submitBitcoinBlock(String blockHashForMergedMining, co.rsk.bitcoinj.
         Block newBlock;
         Sha3Hash key = new Sha3Hash(TypeConverter.removeZeroX(blockHashForMergedMining));
         synchronized (LOCK) {
-            newBlock = blocksWaitingforPoW.get(key);
-            if (newBlock == null) {
+            Block workingBlock = blocksWaitingforPoW.get(key);
+
+            if (workingBlock == null) {
                 logger.warn("Cannot publish block, could not find hash " + blockHashForMergedMining + " in the cache");
                 return;
             }
 
             // just in case, remove all references to this block.
-            if (latestBlock == newBlock) {
+            if (latestBlock == workingBlock) {
                 latestBlock = null;
                 latestblockHashWaitingforPoW = null;
                 currentWork = null;
             }
+
+            // clone the block
+            newBlock = new Block(workingBlock.getEncoded());
+
             logger.debug("blocksWaitingforPoW size " + blocksWaitingforPoW.size());
         }
+
         logger.info("Received block {} {}", newBlock.getNumber(), Hex.toHexString(newBlock.getHash()));
 
         newBlock.setBitcoinMergedMiningHeader(bitcoinMergedMiningBlock.cloneAsHeader().bitcoinSerialize());
@@ -259,7 +265,7 @@ public MinerWork getWork() {
              * currentWork, regardless of what it is.
              */
             synchronized (LOCK) {
-                if (currentWork != work || currentWork == null) {
+                if (currentWork != work ||  currentWork == null) {
                     return currentWork;
                 }
                 currentWork = new MinerWork(currentWork.getBlockHashForMergedMining(), currentWork.getTarget(),
@@ -270,6 +276,11 @@ public MinerWork getWork() {
         return work;
     }
 
+    @VisibleForTesting
+    public void setWork(MinerWork work) {
+        this.currentWork = work;
+    }
+
     public MinerWork updateGetWork(@Nonnull final Block block, @Nonnull final boolean notify) {
         Sha3Hash blockMergedMiningHash = new Sha3Hash(block.getHashForMergedMining());
 

diff --git a/rskj-core/src/test/java/co/rsk/mine/MinerManagerTest.java b/rskj-core/src/test/java/co/rsk/mine/MinerManagerTest.java
@@ -32,6 +32,8 @@
 import org.junit.Assert;
 import org.junit.Test;
 
+import java.util.Arrays;
+import java.util.List;
 import java.util.concurrent.Callable;
 
 /**
@@ -98,6 +100,43 @@ public void refreshWorkRunTwice() {
         Assert.assertEquals(2, blockchain.getBestBlock().getNumber());
     }
 
+    @Test
+    public void mineBlockTwiceReusingTheSameWork() {
+        World world = new World();
+        Blockchain blockchain = world.getBlockChain();
+
+        Assert.assertEquals(0, blockchain.getBestBlock().getNumber());
+
+        MinerServerImpl minerServer = getMinerServer(blockchain);
+        MinerClientImpl minerClient = getMinerClient(minerServer);
+
+        minerServer.buildBlockToMine(blockchain.getBestBlock(), false);
+
+        MinerWork minerWork = minerServer.getWork();
+
+        Assert.assertNotNull(minerWork);
+
+        Assert.assertTrue(minerClient.mineBlock());
+
+        Block bestBlock = blockchain.getBestBlock();
+
+        Assert.assertNotNull(bestBlock);
+        Assert.assertEquals(1, bestBlock.getNumber());
+
+        // reuse the same work
+        Assert.assertNull(minerServer.getWork());
+        minerServer.setWork(minerWork);
+        Assert.assertNotNull(minerServer.getWork());
+
+        Assert.assertTrue(minerClient.mineBlock());
+
+        List<Block> blocks = blockchain.getBlocksByNumber(1);
+
+        Assert.assertNotNull(blocks);
+        Assert.assertEquals(2, blocks.size());
+        Assert.assertFalse(Arrays.equals(blocks.get(0).getHash(), blocks.get(1).getHash()));
+    }
+
     @Test
     public void mineBlockWhileSyncingBlocks() {
         World world = new World();