From 62f406adb47971ceca29b9ea062f077f34827f4d Mon Sep 17 00:00:00 2001
From: Herr Seppia <seppia@dusk.network>
Date: Wed, 27 Jul 2022 16:00:24 +0200
Subject: [PATCH] Reintroduce artificial delay on block generator

---
 harness/engine/profiles.go                       |  1 +
 pkg/config/groups.go                             |  2 ++
 .../blockgenerator/candidate/blockgenerator.go   | 16 ++++++++++------
 3 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/harness/engine/profiles.go b/harness/engine/profiles.go
index fb5ee99c8..7aad87a09 100644
--- a/harness/engine/profiles.go
+++ b/harness/engine/profiles.go
@@ -64,6 +64,7 @@ func Profile1(index int, node *DuskNode, consensusKeysPath string) {
 	// viper.Set("mempool.preallocTxs", "100")
 	viper.Set("mempool.poolType", "diskpool")
 	viper.Set("mempool.diskpoolDir", node.Dir+"/mempool.db")
+	viper.Set("mempool.extractionDelaySecs", "3")
 
 	viper.Set("mempool.maxInvItems", "10000")
 	viper.Set("mempool.propagateTimeout", "100ms")
diff --git a/pkg/config/groups.go b/pkg/config/groups.go
index f2b8813a9..1af48d137 100644
--- a/pkg/config/groups.go
+++ b/pkg/config/groups.go
@@ -137,6 +137,8 @@ type mempoolConfiguration struct {
 
 	// Enables mempool updates at startup
 	Updates updates
+
+	ExtractionDelaySecs uint32
 }
 
 type updates struct {
diff --git a/pkg/core/consensus/blockgenerator/candidate/blockgenerator.go b/pkg/core/consensus/blockgenerator/candidate/blockgenerator.go
index 24b160272..629be1b99 100644
--- a/pkg/core/consensus/blockgenerator/candidate/blockgenerator.go
+++ b/pkg/core/consensus/blockgenerator/candidate/blockgenerator.go
@@ -128,9 +128,14 @@ func (bg *generator) execute(ctx context.Context, txs []transactions.ContractCal
 }
 
 // fetchOrTimeout will keep trying to FetchMempoolTxs() until either
-// we get some txs or or the timeout expires.
-func (bg *generator) FetchOrTimeout(keys [][]byte) ([]transactions.ContractCall, error) {
-	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
+// we get some txs or the timeout expires.
+func (bg *generator) fetchOrTimeout(keys [][]byte) ([]transactions.ContractCall, error) {
+	delay := config.Get().Mempool.ExtractionDelaySecs
+	if delay == 0 {
+		return bg.FetchMempoolTxs(keys)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), time.Duration(delay)*time.Second)
 	defer cancel()
 
 	tick := time.NewTicker(500 * time.Millisecond)
@@ -139,8 +144,7 @@ func (bg *generator) FetchOrTimeout(keys [][]byte) ([]transactions.ContractCall,
 	for {
 		select {
 		case <-ctx.Done():
-			txs, err := bg.FetchMempoolTxs(keys)
-			return txs, err
+			return bg.FetchMempoolTxs(keys)
 		case <-tick.C:
 			txs, err := bg.FetchMempoolTxs(keys)
 			if err != nil {
@@ -157,7 +161,7 @@ func (bg *generator) FetchOrTimeout(keys [][]byte) ([]transactions.ContractCall,
 // GenerateBlock generates a candidate block, by constructing the header and filling it
 // with transactions from the mempool.
 func (bg *generator) GenerateBlock(round uint64, seed, prevBlockHash []byte, prevBlockTimestamp int64, keys [][]byte) (*block.Block, error) {
-	txs, err := bg.FetchMempoolTxs(keys)
+	txs, err := bg.fetchOrTimeout(keys)
 	if err != nil {
 		return nil, err
 	}