[PAN-3023] Add command line option for target gas limit

acceptance-tests/src/test/java/tech/pegasys/pantheon/tests/acceptance/dsl/node/ThreadPantheonNodeRunner.java

@@ -119,6 +119,7 @@ public void startNode(final PantheonNode node) {
               .ethProtocolConfiguration(EthProtocolConfiguration.defaultConfig())
               .clock(Clock.systemUTC())
               .isRevertReasonEnabled(node.isRevertReasonEnabled())
+              .gasLimitCalculator((gasLimit) -> gasLimit)
               .build();
     } catch (final IOException e) {
       throw new RuntimeException("Error building PantheonController", e);

consensus/clique/src/main/java/tech/pegasys/pantheon/consensus/clique/blockcreation/CliqueMinerExecutor.java

@@ -53,14 +53,16 @@ public CliqueMinerExecutor(
       final KeyPair nodeKeys,
       final MiningParameters miningParams,
       final AbstractBlockScheduler blockScheduler,
-      final EpochManager epochManager) {
+      final EpochManager epochManager,
+      final Function<Long, Long> gasLimitCalculator) {
     super(
         protocolContext,
         executorService,
         protocolSchedule,
         pendingTransactions,
         miningParams,
-        blockScheduler);
+        blockScheduler,
+        gasLimitCalculator);
     this.nodeKeys = nodeKeys;
     this.localAddress = Util.publicKeyToAddress(nodeKeys.getPublicKey());
     this.epochManager = epochManager;
@@ -89,7 +91,7 @@ private CliqueBlockMiner createMiner(
                 pendingTransactions,
                 protocolContext,
                 protocolSchedule,
-                (gasLimit) -> gasLimit,
+                gasLimitCalculator,
                 nodeKeys,
                 minTransactionGasPrice,
                 header,

consensus/clique/src/test/java/tech/pegasys/pantheon/consensus/clique/blockcreation/CliqueMinerExecutorTest.java

@@ -98,7 +98,8 @@ public void extraDataCreatedOnEpochBlocksContainsValidators() {
             proposerKeyPair,
             new MiningParameters(AddressHelpers.ofValue(1), Wei.ZERO, vanityData, false),
             mock(CliqueBlockScheduler.class),
-            new EpochManager(EPOCH_LENGTH));
+            new EpochManager(EPOCH_LENGTH),
+            (gasLimit) -> gasLimit);
 
     // NOTE: Passing in the *parent* block, so must be 1 less than EPOCH
     final BlockHeader header = blockHeaderBuilder.number(EPOCH_LENGTH - 1).buildHeader();
@@ -135,7 +136,8 @@ public void extraDataForNonEpochBlocksDoesNotContainValidaors() {
             proposerKeyPair,
             new MiningParameters(AddressHelpers.ofValue(1), Wei.ZERO, vanityData, false),
             mock(CliqueBlockScheduler.class),
-            new EpochManager(EPOCH_LENGTH));
+            new EpochManager(EPOCH_LENGTH),
+            (gasLimit) -> gasLimit);
 
     // Parent block was epoch, so the next block should contain no validators.
     final BlockHeader header = blockHeaderBuilder.number(EPOCH_LENGTH).buildHeader();
@@ -172,7 +174,8 @@ public void shouldUseLatestVanityData() {
             proposerKeyPair,
             new MiningParameters(AddressHelpers.ofValue(1), Wei.ZERO, initialVanityData, false),
             mock(CliqueBlockScheduler.class),
-            new EpochManager(EPOCH_LENGTH));
+            new EpochManager(EPOCH_LENGTH),
+            (gasLimit) -> gasLimit);
 
     executor.setExtraData(modifiedVanityData);
     final BytesValue extraDataBytes = executor.calculateExtraData(blockHeaderBuilder.buildHeader());

ethereum/blockcreation/src/main/java/tech/pegasys/pantheon/ethereum/blockcreation/AbstractMinerExecutor.java

@@ -25,6 +25,7 @@
 
 import java.util.Optional;
 import java.util.concurrent.ExecutorService;
+import java.util.function.Function;
 
 public abstract class AbstractMinerExecutor<
     C, M extends BlockMiner<C, ? extends AbstractBlockCreator<C>>> {
@@ -34,6 +35,7 @@ public abstract class AbstractMinerExecutor<
   protected final ProtocolSchedule<C> protocolSchedule;
   protected final PendingTransactions pendingTransactions;
   protected final AbstractBlockScheduler blockScheduler;
+  protected final Function<Long, Long> gasLimitCalculator;
 
   protected volatile BytesValue extraData;
   protected volatile Wei minTransactionGasPrice;
@@ -44,14 +46,16 @@ public AbstractMinerExecutor(
       final ProtocolSchedule<C> protocolSchedule,
       final PendingTransactions pendingTransactions,
       final MiningParameters miningParams,
-      final AbstractBlockScheduler blockScheduler) {
+      final AbstractBlockScheduler blockScheduler,
+      final Function<Long, Long> gasLimitCalculator) {
     this.protocolContext = protocolContext;
     this.executorService = executorService;
     this.protocolSchedule = protocolSchedule;
     this.pendingTransactions = pendingTransactions;
     this.extraData = miningParams.getExtraData();
     this.minTransactionGasPrice = miningParams.getMinTransactionGasPrice();
     this.blockScheduler = blockScheduler;
+    this.gasLimitCalculator = gasLimitCalculator;
   }
 
   public abstract M startAsyncMining(

ethereum/blockcreation/src/main/java/tech/pegasys/pantheon/ethereum/blockcreation/EthHashMinerExecutor.java

@@ -37,14 +37,16 @@ public EthHashMinerExecutor(
       final ProtocolSchedule<Void> protocolSchedule,
       final PendingTransactions pendingTransactions,
       final MiningParameters miningParams,
-      final AbstractBlockScheduler blockScheduler) {
+      final AbstractBlockScheduler blockScheduler,
+      final Function<Long, Long> gasLimitCalculator) {
     super(
         protocolContext,
         executorService,
         protocolSchedule,
         pendingTransactions,
         miningParams,
-        blockScheduler);
+        blockScheduler,
+        gasLimitCalculator);
     this.coinbase = miningParams.getCoinbase();
   }
 
@@ -77,7 +79,7 @@ private EthHashBlockMiner createMiner(
                 pendingTransactions,
                 protocolContext,
                 protocolSchedule,
-                (gasLimit) -> gasLimit,
+                gasLimitCalculator,
                 solver,
                 minTransactionGasPrice,
                 parentHeader);

ethereum/blockcreation/src/test/java/tech/pegasys/pantheon/ethereum/blockcreation/EthHashMinerExecutorTest.java

@@ -49,7 +49,8 @@ public void startingMiningWithoutCoinbaseThrowsException() {
             null,
             pendingTransactions,
             miningParameters,
-            new DefaultBlockScheduler(1, 10, TestClock.fixed()));
+            new DefaultBlockScheduler(1, 10, TestClock.fixed()),
+            (gasLimit) -> gasLimit);
 
     assertThatExceptionOfType(CoinbaseNotSetException.class)
         .isThrownBy(() -> executor.startAsyncMining(Subscribers.create(), null))
@@ -74,7 +75,8 @@ public void settingCoinbaseToNullThrowsException() {
             null,
             pendingTransactions,
             miningParameters,
-            new DefaultBlockScheduler(1, 10, TestClock.fixed()));
+            new DefaultBlockScheduler(1, 10, TestClock.fixed()),
+            (gasLimit) -> gasLimit);
 
     assertThatExceptionOfType(IllegalArgumentException.class)
         .isThrownBy(() -> executor.setCoinbase(null))

pantheon/src/main/java/tech/pegasys/pantheon/cli/PantheonCommand.java

@@ -118,6 +118,7 @@
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.function.Function;
 import java.util.function.Supplier;
 import java.util.stream.Collectors;
 
@@ -633,6 +634,12 @@ void setBannedNodeIds(final List<String> values) {
           "The name of a file containing the private key used to sign privacy marker transactions. If unset, each will be signed with a random key.")
   private final Path privacyMarkerTransactionSigningKeyPath = null;
 
+  @Option(
+      names = {"--target-gas-limit"},
+      description =
+          "Sets target gas limit per block. If set each blocks gas limit will approach this setting over time if the current gas limit is different.")
+  private final Long targetGasLimit = null;
+
   @Option(
       names = {"--tx-pool-max-size"},
       paramLabel = MANDATORY_INTEGER_FORMAT_HELP,
@@ -657,6 +664,7 @@ void setBannedNodeIds(final List<String> values) {
   private MetricsConfiguration metricsConfiguration;
   private Optional<PermissioningConfiguration> permissioningConfiguration;
   private Collection<EnodeURL> staticNodes;
+  private Function<Long, Long> gasLimitCalculator;
   private PantheonController<?> pantheonController;
 
   private final Supplier<ObservableMetricsSystem> metricsSystem =
@@ -879,6 +887,7 @@ private PantheonCommand configure() throws Exception {
     webSocketConfiguration = webSocketConfiguration();
     permissioningConfiguration = permissioningConfiguration();
     staticNodes = loadStaticNodes();
+    gasLimitCalculator = gasLimitCalculator();
     logger.info("Connecting to {} static nodes.", staticNodes.size());
     logger.trace("Static Nodes = {}", staticNodes);
     final List<URI> enodeURIs =
@@ -946,7 +955,8 @@ public PantheonControllerBuilder<?> getControllerBuilder() {
           .clock(Clock.systemUTC())
           .isRevertReasonEnabled(isRevertReasonEnabled)
           .isPruningEnabled(isPruningEnabled)
-          .pruningConfiguration(buildPruningConfiguration());
+          .pruningConfiguration(buildPruningConfiguration())
+          .gasLimitCalculator(gasLimitCalculator);
     } catch (final IOException e) {
       throw new ExecutionException(this.commandLine, "Invalid path", e);
     }
@@ -1536,6 +1546,31 @@ private Set<EnodeURL> loadStaticNodes() throws IOException {
     return StaticNodesParser.fromPath(staticNodesPath);
   }
 
+  private Function<Long, Long> gasLimitCalculator() {
+    final long targetGasLimit = this.targetGasLimit == null ? 0L : this.targetGasLimit;
+    final long adjustmentFactor = 1024L;
+
+    if (targetGasLimit > 0L) {
+      return (gasLimit) -> {
+        long newGasLimit;
+
+        if (targetGasLimit > gasLimit) {
+          newGasLimit = Math.min(targetGasLimit, gasLimit + adjustmentFactor);
+        } else if (targetGasLimit < gasLimit) {
+          newGasLimit = Math.max(targetGasLimit, gasLimit - adjustmentFactor);
+        } else {
+          return gasLimit;
+        }
+
+        logger.debug("Adjusting block gas limit from {} to {}", gasLimit, newGasLimit);
+
+        return newGasLimit;
+      };
+    } else {
+      return gasLimit -> gasLimit;
+    }
+  }
+
   public PantheonExceptionHandler exceptionHandler() {
     return new PantheonExceptionHandler(this::getLogLevel);
   }

pantheon/src/main/java/tech/pegasys/pantheon/controller/CliquePantheonControllerBuilder.java

@@ -94,7 +94,8 @@ protected MiningCoordinator createMiningCoordinator(
                 protocolContext.getConsensusState().getVoteTallyCache(),
                 localAddress,
                 secondsBetweenBlocks),
-            epochManager);
+            epochManager,
+            gasLimitCalculator);
     final CliqueMiningCoordinator miningCoordinator =
         new CliqueMiningCoordinator(
             protocolContext.getBlockchain(),

pantheon/src/main/java/tech/pegasys/pantheon/controller/IbftPantheonControllerBuilder.java

@@ -111,7 +111,7 @@ protected MiningCoordinator createMiningCoordinator(
 
     final IbftBlockCreatorFactory blockCreatorFactory =
         new IbftBlockCreatorFactory(
-            (gasLimit) -> gasLimit,
+            gasLimitCalculator,
             transactionPool.getPendingTransactions(),
             protocolContext,
             protocolSchedule,

pantheon/src/main/java/tech/pegasys/pantheon/controller/MainnetPantheonControllerBuilder.java

@@ -56,7 +56,8 @@ protected MiningCoordinator createMiningCoordinator(
             new DefaultBlockScheduler(
                 MainnetBlockHeaderValidator.MINIMUM_SECONDS_SINCE_PARENT,
                 MainnetBlockHeaderValidator.TIMESTAMP_TOLERANCE_S,
-                clock));
+                clock),
+            gasLimitCalculator);
 
     final EthHashMiningCoordinator miningCoordinator =
         new EthHashMiningCoordinator(protocolContext.getBlockchain(), executor, syncState);

pantheon/src/main/java/tech/pegasys/pantheon/controller/PantheonControllerBuilder.java

@@ -63,6 +63,7 @@
 import java.util.Optional;
 import java.util.OptionalLong;
 import java.util.concurrent.Executors;
+import java.util.function.Function;
 
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import org.apache.logging.log4j.LogManager;
@@ -84,6 +85,7 @@ public abstract class PantheonControllerBuilder<C> {
   protected Clock clock;
   protected KeyPair nodeKeys;
   protected boolean isRevertReasonEnabled;
+  protected Function<Long, Long> gasLimitCalculator;
   private StorageProvider storageProvider;
   private final List<Runnable> shutdownActions = new ArrayList<>();
   private RocksDbConfiguration rocksDbConfiguration;
@@ -181,6 +183,12 @@ public PantheonControllerBuilder<C> pruningConfiguration(
     return this;
   }
 
+  public PantheonControllerBuilder<C> gasLimitCalculator(
+      final Function<Long, Long> gasLimitCalculator) {
+    this.gasLimitCalculator = gasLimitCalculator;
+    return this;
+  }
+
   public PantheonController<C> build() throws IOException {
     checkNotNull(genesisConfig, "Missing genesis config");
     checkNotNull(syncConfig, "Missing sync config");
@@ -193,6 +201,7 @@ public PantheonController<C> build() throws IOException {
     checkNotNull(clock, "Mising clock");
     checkNotNull(transactionPoolConfiguration, "Missing transaction pool configuration");
     checkNotNull(nodeKeys, "Missing node keys");
+    checkNotNull(gasLimitCalculator, "Missing gas limit calculator");
     checkArgument(
         storageProvider != null || rocksDbConfiguration != null,
         "Must supply either a storage provider or RocksDB configuration");

pantheon/src/test/java/tech/pegasys/pantheon/PrivacyTest.java

@@ -66,6 +66,7 @@ public void privacyPrecompiled() throws IOException {
             .clock(TestClock.fixed())
             .privacyParameters(privacyParameters)
             .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+            .gasLimitCalculator(gasLimit -> gasLimit)
             .build();
 
     final Address privacyContractAddress = Address.privacyPrecompiled(ADDRESS);

pantheon/src/test/java/tech/pegasys/pantheon/RunnerTest.java

@@ -135,6 +135,7 @@ private void syncFromGenesis(final SyncMode mode) throws Exception {
             .clock(TestClock.fixed())
             .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
             .storageProvider(createKeyValueStorageProvider(dbAhead))
+            .gasLimitCalculator(gasLimit -> gasLimit)
             .build()) {
       setupState(blockCount, controller.getProtocolSchedule(), controller.getProtocolContext());
     }
@@ -154,6 +155,7 @@ private void syncFromGenesis(final SyncMode mode) throws Exception {
             .clock(TestClock.fixed())
             .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
             .storageProvider(createKeyValueStorageProvider(dbAhead))
+            .gasLimitCalculator(gasLimit -> gasLimit)
             .build();
     final String listenHost = InetAddress.getLoopbackAddress().getHostAddress();
     final JsonRpcConfiguration aheadJsonRpcConfiguration = jsonRpcConfiguration();
@@ -212,6 +214,7 @@ private void syncFromGenesis(final SyncMode mode) throws Exception {
               .privacyParameters(PrivacyParameters.DEFAULT)
               .clock(TestClock.fixed())
               .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+              .gasLimitCalculator(gasLimit -> gasLimit)
               .build();
       final EnodeURL enode = runnerAhead.getLocalEnode().get();
       final EthNetworkConfig behindEthNetworkConfiguration =

pantheon/src/test/java/tech/pegasys/pantheon/chainexport/RlpBlockExporterTest.java

@@ -88,6 +88,7 @@ private static PantheonController<?> createController() throws IOException {
         .dataDirectory(dataDir)
         .clock(TestClock.fixed())
         .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+        .gasLimitCalculator(gasLimit -> gasLimit)
         .build();
   }
 

pantheon/src/test/java/tech/pegasys/pantheon/chainimport/JsonBlockImporterTest.java

@@ -425,6 +425,7 @@ protected PantheonController<?> createController(final GenesisConfigFile genesis
         .dataDirectory(dataDir)
         .clock(TestClock.fixed())
         .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+        .gasLimitCalculator(gasLimit -> gasLimit)
         .build();
   }
 }

pantheon/src/test/java/tech/pegasys/pantheon/chainimport/RlpBlockImporterTest.java

@@ -66,6 +66,7 @@ public void blockImport() throws IOException {
             .dataDirectory(dataDir)
             .clock(TestClock.fixed())
             .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+            .gasLimitCalculator(gasLimit -> gasLimit)
             .build();
     final RlpBlockImporter.ImportResult result =
         rlpBlockImporter.importBlockchain(source, targetController);
@@ -105,6 +106,7 @@ public void ibftImport() throws IOException {
             .dataDirectory(dataDir)
             .clock(TestClock.fixed())
             .transactionPoolConfiguration(TransactionPoolConfiguration.builder().build())
+            .gasLimitCalculator(gasLimit -> gasLimit)
             .build();
     final RlpBlockImporter.ImportResult result =
         rlpBlockImporter.importBlockchain(source, controller);

pantheon/src/test/java/tech/pegasys/pantheon/cli/CommandTestAbstract.java

@@ -154,6 +154,7 @@ public void initMocks() throws Exception {
     when(mockControllerBuilder.isRevertReasonEnabled(false)).thenReturn(mockControllerBuilder);
     when(mockControllerBuilder.isPruningEnabled(anyBoolean())).thenReturn(mockControllerBuilder);
     when(mockControllerBuilder.pruningConfiguration(any())).thenReturn(mockControllerBuilder);
+    when(mockControllerBuilder.gasLimitCalculator(any())).thenReturn(mockControllerBuilder);
 
     // doReturn used because of generic PantheonController
     doReturn(mockController).when(mockControllerBuilder).build();