From 2e19f7905d486e6631ba0527cb3de03ff3790a0d Mon Sep 17 00:00:00 2001
From: Jim Zhang <jim.zhang@consensys.net>
Date: Sun, 18 Mar 2018 22:48:07 -0400
Subject: [PATCH 1/3] Disable ethash by replacing with ethash.NewFullFake

---
 eth/backend.go | 21 +++++----------------
 1 file changed, 5 insertions(+), 16 deletions(-)

diff --git a/eth/backend.go b/eth/backend.go
index 7fb48c9d0..c8b302bf4 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -235,22 +235,11 @@ func CreateConsensusEngine(ctx *node.ServiceContext, config *Config, chainConfig
 	}
 
 	// Otherwise assume proof-of-work
-	switch {
-	case config.PowFake:
-		log.Warn("Ethash used in fake mode")
-		return ethash.NewFaker()
-	case config.PowTest:
-		log.Warn("Ethash used in test mode")
-		return ethash.NewTester()
-	case config.PowShared:
-		log.Warn("Ethash used in shared mode")
-		return ethash.NewShared()
-	default:
-		engine := ethash.New(ctx.ResolvePath(config.EthashCacheDir), config.EthashCachesInMem, config.EthashCachesOnDisk,
-			config.EthashDatasetDir, config.EthashDatasetsInMem, config.EthashDatasetsOnDisk)
-		engine.SetThreads(-1) // Disable CPU mining
-		return engine
-	}
+	// For Quorum, Raft run as a separate service, so
+	// the Ethereum service still needs a consensus engine,
+	// use the consensus with the lightest overhead
+	log.Warn("Ethash used in full fake mode")
+	return ethash.NewFullFaker()
 }
 
 // APIs returns the collection of RPC services the ethereum package offers.

From c535103027e37128557a1f8b90f9b4be049a5a55 Mon Sep 17 00:00:00 2001
From: Jim Zhang <jim.zhang@consensys.net>
Date: Wed, 18 Apr 2018 17:49:31 -0400
Subject: [PATCH 2/3] Addressing Sam's comment in the PR: make the FullFake
 engine the default so other test/fake flavors can still be used

---
 eth/backend.go | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/eth/backend.go b/eth/backend.go
index c8b302bf4..7bff84663 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -235,11 +235,23 @@ func CreateConsensusEngine(ctx *node.ServiceContext, config *Config, chainConfig
 	}
 
 	// Otherwise assume proof-of-work
-	// For Quorum, Raft run as a separate service, so
-	// the Ethereum service still needs a consensus engine,
-	// use the consensus with the lightest overhead
-	log.Warn("Ethash used in full fake mode")
-	return ethash.NewFullFaker()
+  switch {
+  case config.PowFake:
+          log.Warn("Ethash used in fake mode")
+          return ethash.NewFaker()
+  case config.PowTest:
+          log.Warn("Ethash used in test mode")
+          return ethash.NewTester()
+  case config.PowShared:
+          log.Warn("Ethash used in shared mode")
+          return ethash.NewShared()
+  default:
+          // For Quorum, Raft run as a separate service, so
+          // the Ethereum service still needs a consensus engine,
+          // use the consensus with the lightest overhead
+          log.Warn("Ethash used in full fake mode")
+          return ethash.NewFullFaker()
+  }
 }
 
 // APIs returns the collection of RPC services the ethereum package offers.

From 51274bd368bc93694babe69ee60a5f94758f31ae Mon Sep 17 00:00:00 2001
From: Jim Zhang <jim.zhang@consensys.net>
Date: Thu, 19 Apr 2018 15:02:05 -0400
Subject: [PATCH 3/3] reformatted with 'gofmt'

---
 eth/backend.go | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/eth/backend.go b/eth/backend.go
index 7bff84663..3e970b28b 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -235,23 +235,23 @@ func CreateConsensusEngine(ctx *node.ServiceContext, config *Config, chainConfig
 	}
 
 	// Otherwise assume proof-of-work
-  switch {
-  case config.PowFake:
-          log.Warn("Ethash used in fake mode")
-          return ethash.NewFaker()
-  case config.PowTest:
-          log.Warn("Ethash used in test mode")
-          return ethash.NewTester()
-  case config.PowShared:
-          log.Warn("Ethash used in shared mode")
-          return ethash.NewShared()
-  default:
-          // For Quorum, Raft run as a separate service, so
-          // the Ethereum service still needs a consensus engine,
-          // use the consensus with the lightest overhead
-          log.Warn("Ethash used in full fake mode")
-          return ethash.NewFullFaker()
-  }
+	switch {
+	case config.PowFake:
+		log.Warn("Ethash used in fake mode")
+		return ethash.NewFaker()
+	case config.PowTest:
+		log.Warn("Ethash used in test mode")
+		return ethash.NewTester()
+	case config.PowShared:
+		log.Warn("Ethash used in shared mode")
+		return ethash.NewShared()
+	default:
+		// For Quorum, Raft run as a separate service, so
+		// the Ethereum service still needs a consensus engine,
+		// use the consensus with the lightest overhead
+		log.Warn("Ethash used in full fake mode")
+		return ethash.NewFullFaker()
+	}
 }
 
 // APIs returns the collection of RPC services the ethereum package offers.