diff --git a/hack/krmFunctionBenchmark/.gitignore b/hack/krmFunctionBenchmark/.gitignore
new file mode 100644
index 000000000..392baaab0
--- /dev/null
+++ b/hack/krmFunctionBenchmark/.gitignore
@@ -0,0 +1,3 @@
+node_modules
+dist
+example_tshirt/execfn/tshirt
diff --git a/hack/krmFunctionBenchmark/benchmark.sh b/hack/krmFunctionBenchmark/benchmark.sh
new file mode 100755
index 000000000..a2c5e8cc5
--- /dev/null
+++ b/hack/krmFunctionBenchmark/benchmark.sh
@@ -0,0 +1,78 @@
+#! /bin/bash
+
+set -e
+
+KUSTOMIZE_EXEC=kustomize
+KUSTOMIZE_FLAGS="build --enable_alpha_plugins --enable-exec"
+
+function build_label_namespace_exec {
+    cd label_namespace/execfn
+    . build.sh
+    cd -
+}
+
+function build_tshirt_exec {
+    cd example_tshirt/execfn
+    . build.sh
+    cd -
+}
+
+function build_exec {
+    echo "Building exec functions..."
+    build_tshirt_exec
+    build_label_namespace_exec
+    echo "Done. Start running benchmark."
+}
+
+function run_fn {
+    local loop=$1
+    local type=$2
+    local dir=$3
+    echo -e "=== Running ${type} ${loop} times ==="
+    cd $dir
+    local begin_time=$(date +%s%N)
+    for ((i = 0; i < $loop; i++))
+    do
+        $KUSTOMIZE_EXEC $KUSTOMIZE_FLAGS > /dev/null
+        echo -en "\r$i/$loop"
+    done
+    local end_time=$(date +%s%N)
+    local time_diff=$(($end_time - $begin_time))
+    local time_diff_s=$(echo "${time_diff} / 1000 / 1000 / 1000" | bc -l)
+    echo -e "\n=== Time used: ==="
+    echo "${time_diff_s}s"
+    cd -
+}
+
+function run_label_namespace_benchmark {
+    local loop=$1
+    run_fn $loop "Label Namespace Transformer Exec Function" "label_namespace/execfn"
+    run_fn $loop "Label Namespace Transformer Container Function" "label_namespace/containerfn"
+}
+
+function run_tshirt_benchmark {
+    local loop=$1
+    run_fn $loop "T-shirt Example Exec Function" "example_tshirt/execfn"
+    run_fn $loop "T-shirt Example Container Function" "example_tshirt/containerfn"
+}
+
+if [ "$1" != "--doIt" ]; then
+  echo "Usage: $0 --doIt"
+  echo " "
+  echo "This script measures performance of kustomize containerized"
+  echo "functions (KRM config functions) implementation."
+  echo "It does so by running functions in local executable mode and"
+  echo "in container mode for 10, 100 and 1000 times. The time"
+  echo "used in these 2 modes are recorded."
+  exit 1
+fi
+
+loops=(10 100 1000)
+
+build_exec
+
+for l in "${loops[@]}"
+do
+    run_label_namespace_benchmark $l
+    run_tshirt_benchmark $l
+done
diff --git a/hack/krmFunctionBenchmark/cleanup.sh b/hack/krmFunctionBenchmark/cleanup.sh
new file mode 100755
index 000000000..f7dded0da
--- /dev/null
+++ b/hack/krmFunctionBenchmark/cleanup.sh
@@ -0,0 +1,12 @@
+#! /bin/bash
+set -e
+echo "You may need to run as root to clean."
+
+rm -rf example_tshirt/execfn/tshirt label_namespace/execfn/dist label_namespace/execfn/node_modules
+
+if [ "$1" == "--image" ]; then
+    docker image rm label_namespace_build:latest
+    docker image rm tshirt_example_build:latest
+fi
+
+echo "Done"
diff --git a/hack/krmFunctionBenchmark/example_tshirt/containerfn/data.yaml b/hack/krmFunctionBenchmark/example_tshirt/containerfn/data.yaml
new file mode 100644
index 000000000..fcacb88f4
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/containerfn/data.yaml
@@ -0,0 +1,20 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: nginx
+  labels:
+    app: nginx
+  annotations:
+    tshirt-size: small # this injects the resource reservations
+spec:
+  selector:
+    matchLabels:
+      app: nginx
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx
diff --git a/hack/krmFunctionBenchmark/example_tshirt/containerfn/kustomization.yaml b/hack/krmFunctionBenchmark/example_tshirt/containerfn/kustomization.yaml
new file mode 100644
index 000000000..499359fd8
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/containerfn/kustomization.yaml
@@ -0,0 +1,4 @@
+resources:
+- data.yaml
+transformers:
+- transf.yaml
diff --git a/hack/krmFunctionBenchmark/example_tshirt/containerfn/transf.yaml b/hack/krmFunctionBenchmark/example_tshirt/containerfn/transf.yaml
new file mode 100644
index 000000000..addbb66e4
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/containerfn/transf.yaml
@@ -0,0 +1,8 @@
+apiVersion: examples.config.kubernetes.io/v1beta1
+kind: tshirt
+metadata:
+  name: tshirt
+  annotations:
+    config.kubernetes.io/function: |-
+      container:
+        image: gcr.io/kustomize-functions/example-tshirt:v0.2.0
diff --git a/hack/krmFunctionBenchmark/example_tshirt/execfn/Dockerfile b/hack/krmFunctionBenchmark/example_tshirt/execfn/Dockerfile
new file mode 100644
index 000000000..4ed5d92a6
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/execfn/Dockerfile
@@ -0,0 +1,16 @@
+FROM alpine:latest
+
+ENV BUILD_HOME=/usr/local/build
+RUN apk update && apk add --no-cache git go
+
+RUN mkdir -p $BUILD_HOME
+
+WORKDIR $BUILD_HOME
+
+RUN git clone https://github.com/kubernetes-sigs/kustomize.git .
+RUN git checkout tags/kustomize/v3.6.1
+WORKDIR $BUILD_HOME/functions/examples/injection-tshirt-sizes/image/
+
+ENV CGO_ENABLED=0
+RUN go mod download
+RUN go build -o tshirt .
diff --git a/hack/krmFunctionBenchmark/example_tshirt/execfn/build.sh b/hack/krmFunctionBenchmark/example_tshirt/execfn/build.sh
new file mode 100755
index 000000000..4795418c3
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/execfn/build.sh
@@ -0,0 +1,9 @@
+#! /bin/bash
+
+IMAGE_LABEL="tshirt_example_build:latest"
+BUILD_HOME=/usr/local/build
+
+docker build -t $IMAGE_LABEL .
+
+docker run --rm -v $(pwd):/out $IMAGE_LABEL \
+    cp -r $BUILD_HOME/functions/examples/injection-tshirt-sizes/image/tshirt /out
diff --git a/hack/krmFunctionBenchmark/example_tshirt/execfn/data.yaml b/hack/krmFunctionBenchmark/example_tshirt/execfn/data.yaml
new file mode 100644
index 000000000..fcacb88f4
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/execfn/data.yaml
@@ -0,0 +1,20 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: nginx
+  labels:
+    app: nginx
+  annotations:
+    tshirt-size: small # this injects the resource reservations
+spec:
+  selector:
+    matchLabels:
+      app: nginx
+  template:
+    metadata:
+      labels:
+        app: nginx
+    spec:
+      containers:
+      - name: nginx
+        image: nginx
diff --git a/hack/krmFunctionBenchmark/example_tshirt/execfn/kustomization.yaml b/hack/krmFunctionBenchmark/example_tshirt/execfn/kustomization.yaml
new file mode 100644
index 000000000..499359fd8
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/execfn/kustomization.yaml
@@ -0,0 +1,4 @@
+resources:
+- data.yaml
+transformers:
+- transf.yaml
diff --git a/hack/krmFunctionBenchmark/example_tshirt/execfn/transf.yaml b/hack/krmFunctionBenchmark/example_tshirt/execfn/transf.yaml
new file mode 100644
index 000000000..e5ab62278
--- /dev/null
+++ b/hack/krmFunctionBenchmark/example_tshirt/execfn/transf.yaml
@@ -0,0 +1,8 @@
+apiVersion: examples.config.kubernetes.io/v1beta1
+kind: tshirt
+metadata:
+  name: tshirt
+  annotations:
+    config.kubernetes.io/function: |-
+      exec:
+        path: ./tshirt
diff --git a/hack/krmFunctionBenchmark/label_namespace/containerfn/containerfn.yaml b/hack/krmFunctionBenchmark/label_namespace/containerfn/containerfn.yaml
new file mode 100644
index 000000000..a3417d2b3
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/containerfn/containerfn.yaml
@@ -0,0 +1,11 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: label_namespace
+  annotations:
+    config.kubernetes.io/function: |-
+      container:
+        image: gcr.io/kpt-functions/label-namespace@sha256:4f030738d6d25a207641ca517916431517578bd0eb8d98a8bde04e3bb9315dcd
+data:
+  label_name: my-ns-name
+  label_value: function-test
diff --git a/hack/krmFunctionBenchmark/label_namespace/containerfn/data1.yaml b/hack/krmFunctionBenchmark/label_namespace/containerfn/data1.yaml
new file mode 100644
index 000000000..4cb279baf
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/containerfn/data1.yaml
@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: my-namespace
diff --git a/hack/krmFunctionBenchmark/label_namespace/containerfn/data2.yaml b/hack/krmFunctionBenchmark/label_namespace/containerfn/data2.yaml
new file mode 100644
index 000000000..c731475f2
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/containerfn/data2.yaml
@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: another-namespace
diff --git a/hack/krmFunctionBenchmark/label_namespace/containerfn/kustomization.yaml b/hack/krmFunctionBenchmark/label_namespace/containerfn/kustomization.yaml
new file mode 100644
index 000000000..e729f717f
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/containerfn/kustomization.yaml
@@ -0,0 +1,5 @@
+resources:
+- data1.yaml
+- data2.yaml
+transformers:
+- containerfn.yaml
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/Dockerfile b/hack/krmFunctionBenchmark/label_namespace/execfn/Dockerfile
new file mode 100644
index 000000000..4e74861f6
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/Dockerfile
@@ -0,0 +1,15 @@
+FROM alpine:latest
+
+ENV BUILD_HOME=/usr/local/build
+RUN apk update && apk add --no-cache git nodejs npm
+RUN npm install -g typescript
+
+RUN mkdir -p $BUILD_HOME
+
+WORKDIR $BUILD_HOME
+
+RUN git clone https://github.com/GoogleContainerTools/kpt-functions-sdk.git .
+RUN git checkout tags/release-kpt-functions-v0.14.2
+WORKDIR $BUILD_HOME/ts/hello-world/
+RUN npm install
+RUN npm run build
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/build.sh b/hack/krmFunctionBenchmark/label_namespace/execfn/build.sh
new file mode 100755
index 000000000..c7e461db5
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/build.sh
@@ -0,0 +1,9 @@
+#! /bin/bash
+
+IMAGE_LABEL="label_namespace_build:latest"
+BUILD_HOME=/usr/local/build
+
+docker build -t $IMAGE_LABEL .
+
+docker run --rm -v $(pwd):/out $IMAGE_LABEL \
+    cp -r $BUILD_HOME/ts/hello-world/dist $BUILD_HOME/ts/hello-world/node_modules /out
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/data1.yaml b/hack/krmFunctionBenchmark/label_namespace/execfn/data1.yaml
new file mode 100644
index 000000000..4cb279baf
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/data1.yaml
@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: my-namespace
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/data2.yaml b/hack/krmFunctionBenchmark/label_namespace/execfn/data2.yaml
new file mode 100644
index 000000000..c731475f2
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/data2.yaml
@@ -0,0 +1,4 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: another-namespace
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/execfn.yaml b/hack/krmFunctionBenchmark/label_namespace/execfn/execfn.yaml
new file mode 100644
index 000000000..b08055823
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/execfn.yaml
@@ -0,0 +1,11 @@
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: label_namespace
+  annotations:
+    config.kubernetes.io/function: |-
+      exec:
+        path: ./fn.sh
+data:
+  label_name: my-ns-name
+  label_value: function-test
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/fn.sh b/hack/krmFunctionBenchmark/label_namespace/execfn/fn.sh
new file mode 100755
index 000000000..de2d233b3
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/fn.sh
@@ -0,0 +1,3 @@
+#! /bin/bash
+
+node ./dist/label_namespace_run.js
diff --git a/hack/krmFunctionBenchmark/label_namespace/execfn/kustomization.yaml b/hack/krmFunctionBenchmark/label_namespace/execfn/kustomization.yaml
new file mode 100644
index 000000000..ecc941a74
--- /dev/null
+++ b/hack/krmFunctionBenchmark/label_namespace/execfn/kustomization.yaml
@@ -0,0 +1,5 @@
+resources:
+- data1.yaml
+- data2.yaml
+transformers:
+- execfn.yaml
diff --git a/hack/krmFunctionBenchmark/readme.md b/hack/krmFunctionBenchmark/readme.md
new file mode 100644
index 000000000..cb3e8eb5a
--- /dev/null
+++ b/hack/krmFunctionBenchmark/readme.md
@@ -0,0 +1,28 @@
+# Benchmark for KRM functions in Kustomize
+
+## Prerequisites
+
+ - [kustomize v3.7.0 or higher](https://kubernetes-sigs.github.io/kustomize/installation) (support for KRM Config Functions).
+ - [docker](https://github.com/kubernetes-sigs/kustomize/pull/docker.com)
+
+## How to run
+
+```bash
+./benchmark.sh
+```
+
+The script will build the exec version of function via container and then run 10, 100 and 1000 times of exec version and container version and then print out the time used by both versions.
+
+```bash
+./cleanup.sh
+```
+Will remove the built exec version of the function. Add flag `--image` to remove the images that used to build exec function.
+
+## Functions in the benchmark
+
+Two functions are used:
+
+ - `gcr.io/kustomize-functions/example-tshirt` ([link](https://github.com/kubernetes-sigs/kustomize/blob/master/functions/examples/injection-tshirt-sizes/image/main.go))
+ - `gcr.io/kpt-functions/label-namespace`	 ([link](https://github.com/GoogleContainerTools/kpt-functions-sdk/blob/master/ts/hello-world/src/label_namespace.ts))
+
+ `example-tshirt` is a Go function. `label-namespace` is a JS function. Both of them are used as transformers.