From 0128e805c5dfafa37078f7e00b5bfc8e465546b9 Mon Sep 17 00:00:00 2001
From: Valentin Staykov <79150443+V-Staykov@users.noreply.github.com>
Date: Mon, 9 Dec 2024 17:04:04 +0200
Subject: [PATCH] perf: remove unneded mem alloc in combine collectors (#1546)
 (#1547)

---
 core/vm/zk_batch_counters.go       |  5 ++++-
 core/vm/zk_counters.go             |  6 ++++++
 core/vm/zk_transaction_counters.go | 12 ++++++++++--
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/core/vm/zk_batch_counters.go b/core/vm/zk_batch_counters.go
index 228d6000335..ea5f708ef44 100644
--- a/core/vm/zk_batch_counters.go
+++ b/core/vm/zk_batch_counters.go
@@ -293,12 +293,15 @@ func (bcc *BatchCounterCollector) CombineCollectorsNoChanges() Counters {
 		}
 	}
 
+	txCounters := NewCounters()
 	for _, tx := range bcc.transactions {
-		txCounters := tx.CombineCounters()
+		_ = tx.CombineCountersInto(&txCounters)
 		for k, v := range txCounters {
 			combined[k].used += v.used
 			combined[k].remaining -= v.used
 		}
+
+		txCounters.NullateUsed()
 	}
 
 	return combined
diff --git a/core/vm/zk_counters.go b/core/vm/zk_counters.go
index 258a911b413..2096d1b72a1 100644
--- a/core/vm/zk_counters.go
+++ b/core/vm/zk_counters.go
@@ -83,6 +83,12 @@ func NewCountersFromUsedArray(used []int) *Counters {
 	return &res
 }
 
+func (c Counters) NullateUsed() {
+	for _, v := range c {
+		v.used = 0
+	}
+}
+
 func (c Counters) UsedAsString() string {
 	res := fmt.Sprintf("[%s: %v]", CounterKeyNames[SHA], c[SHA].used)
 	res += fmt.Sprintf("[%s: %v]", CounterKeyNames[A], c[A].used)
diff --git a/core/vm/zk_transaction_counters.go b/core/vm/zk_transaction_counters.go
index 5ac7d228e9a..f6abee5f9f0 100644
--- a/core/vm/zk_transaction_counters.go
+++ b/core/vm/zk_transaction_counters.go
@@ -52,11 +52,19 @@ func NewTransactionCounter(transaction types.Transaction, smtMaxLevel int, forkI
 
 func (tc *TransactionCounter) CombineCounters() Counters {
 	combined := NewCounters()
+
+	_ = tc.CombineCountersInto(&combined)
+
+	return combined
+}
+
+func (tc *TransactionCounter) CombineCountersInto(combined *Counters) *Counters {
 	for k := range tc.rlpCounters.counters {
 		val := tc.rlpCounters.counters[k].used + tc.executionCounters.counters[k].used + tc.processingCounters.counters[k].used
-		combined[k] = &Counter{
-			used: val,
+		if (*combined)[k] == nil {
+			(*combined)[k] = &Counter{used: 0}
 		}
+		(*combined)[k].used = val
 	}
 
 	return combined