From c40e55a65e70f9a2850775213230732890a0c105 Mon Sep 17 00:00:00 2001
From: lostluck <13907733+lostluck@users.noreply.github.com>
Date: Wed, 19 Jan 2022 19:02:15 -0800
Subject: [PATCH 1/2] [BEAM-13699] Replace fnv with maphash.

---
 sdks/go/pkg/beam/core/runtime/exec/hash.go      | 4 ++--
 sdks/go/pkg/beam/core/runtime/exec/hash_test.go | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/sdks/go/pkg/beam/core/runtime/exec/hash.go b/sdks/go/pkg/beam/core/runtime/exec/hash.go
index db2d0b612bc5..bdc78b87a971 100644
--- a/sdks/go/pkg/beam/core/runtime/exec/hash.go
+++ b/sdks/go/pkg/beam/core/runtime/exec/hash.go
@@ -19,7 +19,7 @@ import (
 	"encoding/binary"
 	"fmt"
 	"hash"
-	"hash/fnv"
+	"hash/maphash"
 	"math"
 	"reflect"
 
@@ -36,7 +36,7 @@ type elementHasher interface {
 
 func makeElementHasher(c *coder.Coder, wc *coder.WindowCoder) elementHasher {
 	// TODO(lostluck): move to a faster hashing library once we can take dependencies easily.
-	hasher := fnv.New64a()
+	hasher := &maphash.Hash{}
 	we := MakeWindowEncoder(wc)
 	switch c.Kind {
 	case coder.Bytes:
diff --git a/sdks/go/pkg/beam/core/runtime/exec/hash_test.go b/sdks/go/pkg/beam/core/runtime/exec/hash_test.go
index 7d2c3deef145..528dfd07baaf 100644
--- a/sdks/go/pkg/beam/core/runtime/exec/hash_test.go
+++ b/sdks/go/pkg/beam/core/runtime/exec/hash_test.go
@@ -18,7 +18,7 @@ package exec
 import (
 	"encoding/json"
 	"fmt"
-	"hash/fnv"
+	"hash/maphash"
 	"reflect"
 	"strings"
 	"testing"
@@ -32,7 +32,7 @@ import (
 
 func BenchmarkPrimitives(b *testing.B) {
 	var value FullValue
-	myHash := fnv.New64a()
+	myHash := &maphash.Hash{}
 	wfn := window.NewGlobalWindows()
 	we := MakeWindowEncoder(wfn.Coder())
 	b.Run("int", func(b *testing.B) {

From 83fb3b7601f04a48784f9ca5d394388146ea9fcc Mon Sep 17 00:00:00 2001
From: lostluck <13907733+lostluck@users.noreply.github.com>
Date: Thu, 20 Jan 2022 07:56:07 -0800
Subject: [PATCH 2/2] rm comment

---
 sdks/go/pkg/beam/core/runtime/exec/hash.go | 1 -
 1 file changed, 1 deletion(-)

diff --git a/sdks/go/pkg/beam/core/runtime/exec/hash.go b/sdks/go/pkg/beam/core/runtime/exec/hash.go
index bdc78b87a971..70fbfa0b0f9d 100644
--- a/sdks/go/pkg/beam/core/runtime/exec/hash.go
+++ b/sdks/go/pkg/beam/core/runtime/exec/hash.go
@@ -35,7 +35,6 @@ type elementHasher interface {
 }
 
 func makeElementHasher(c *coder.Coder, wc *coder.WindowCoder) elementHasher {
-	// TODO(lostluck): move to a faster hashing library once we can take dependencies easily.
 	hasher := &maphash.Hash{}
 	we := MakeWindowEncoder(wc)
 	switch c.Kind {