diff --git a/api/types/load_traffic.go b/api/types/load_traffic.go
index d5d9a3b..d14dbf7 100644
--- a/api/types/load_traffic.go
+++ b/api/types/load_traffic.go
@@ -4,9 +4,7 @@
 package types
 
 import (
-	"encoding/json"
 	"fmt"
-	"strings"
 
 	apitypes "k8s.io/apimachinery/pkg/types"
 )
@@ -165,10 +163,8 @@ type RequestPatch struct {
 	Name string `json:"name" yaml:"name"`
 	// KeySpaceSize is used to generate random number as name's suffix.
 	KeySpaceSize int `json:"keySpaceSize" yaml:"keySpaceSize"`
-	// PatchType is the type of patch, e.g. "json", "merge", "strategic-merge".
-	PatchType string `json:"patchType" yaml:"patchType"`
-	// Body is the request body, for fields to be changed.
-	Body string `json:"body" yaml:"body"`
+	// ValueSize is the object's size in bytes. how many bytes to patch data
+	ValueSize int `json:"valueSize" yaml:"valueSize"`
 }
 
 // RequestGetPodLog defines GetLog request for target pod.
@@ -362,24 +358,13 @@ func (r *RequestPatch) Validate() error {
 	if r.Name == "" {
 		return fmt.Errorf("name is required")
 	}
-	if r.Body == "" {
-		return fmt.Errorf("body is required")
-	}
-
-	// Validate patch type
-	_, ok := GetPatchType(r.PatchType)
-	if !ok {
-		return fmt.Errorf("unknown patch type: %s (valid types: json, merge, strategic-merge)", r.PatchType)
+	if r.Resource == "" {
+		return fmt.Errorf("resource is required")
 	}
-
-	// Validate JSON body and trim it
-	trimmed := strings.TrimSpace(r.Body)
-	if !json.Valid([]byte(trimmed)) {
-		return fmt.Errorf("invalid JSON in patch body: %q", r.Body)
+	if (r.Resource == "configmaps" || r.Resource == "secrets") && r.ValueSize <= 0 {
+		return fmt.Errorf("valueSize must > 0 for configmaps and secrets, to generate data to be patched")
 	}
 
-	r.Body = trimmed // Store the trimmed body
-
 	return nil
 }
 
diff --git a/contrib/utils/utils.go b/contrib/utils/utils.go
index 92c6718..19c66e3 100644
--- a/contrib/utils/utils.go
+++ b/contrib/utils/utils.go
@@ -6,9 +6,11 @@ package utils
 import (
 	"bytes"
 	"context"
+	"crypto/rand"
 	"encoding/json"
 	"errors"
 	"fmt"
+	"math/big"
 	"net"
 	"os"
 	"sort"
@@ -39,8 +41,27 @@ var (
 	// provider ID for all the virtual nodes so that EKS cloud provider
 	// won't delete our virtual nodes.
 	EKSIdleNodepoolInstanceType = "m4.large"
+	// letterRunes contains the alphabet for random string generation
+	letterRunes = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
 )
 
+// randString generates a random string of specified length
+func RandString(n int) (string, error) {
+	if n <= 0 {
+		return "", fmt.Errorf("length must be positive")
+	}
+
+	b := make([]rune, n)
+	for i := range b {
+		random, err := rand.Int(rand.Reader, big.NewInt(int64(len(letterRunes))))
+		if err != nil {
+			return "", fmt.Errorf("error generating random number: %w", err)
+		}
+		b[i] = letterRunes[int(random.Int64())]
+	}
+	return string(b), nil
+}
+
 // RepeatJobWithPod repeats to deploy 3k pods.
 func RepeatJobWithPod(ctx context.Context, kubeCfgPath string, namespace string,
 	target string, timeoutOpts ...JobTimeoutOpt) {
diff --git a/request/random.go b/request/random.go
index 32012e0..6324c8d 100644
--- a/request/random.go
+++ b/request/random.go
@@ -61,7 +61,7 @@ func NewWeightedRandomRequests(spec *types.LoadProfileSpec) (*WeightedRandomRequ
 		case r.GetPodLog != nil:
 			builder = newRequestGetPodLogBuilder(r.GetPodLog, spec.MaxRetries)
 		case r.Patch != nil:
-			builder = newRequestPatchBuilder(r.Patch, "", spec.MaxRetries)
+			builder = newRequestPatchBuilder(r.Patch, spec.MaxRetries)
 		case r.PostDel != nil:
 			builder = newRequestPostDelBuilder(r.PostDel, "", spec.MaxRetries)
 		default:
@@ -363,33 +363,27 @@ func (b *requestGetPodLogBuilder) Build(cli rest.Interface) Requester {
 }
 
 type requestPatchBuilder struct {
-	version         schema.GroupVersion
-	resource        string
-	resourceVersion string
-	namespace       string
-	name            string
-	keySpaceSize    int
-	patchType       apitypes.PatchType
-	body            interface{}
-	maxRetries      int
+	version      schema.GroupVersion
+	resource     string
+	namespace    string
+	name         string
+	keySpaceSize int
+	valueSize    int
+	maxRetries   int
 }
 
-func newRequestPatchBuilder(src *types.RequestPatch, resourceVersion string, maxRetries int) *requestPatchBuilder {
-	patchType, _ := types.GetPatchType(src.PatchType)
-
+func newRequestPatchBuilder(src *types.RequestPatch, maxRetries int) *requestPatchBuilder {
 	return &requestPatchBuilder{
 		version: schema.GroupVersion{
 			Group:   src.Group,
 			Version: src.Version,
 		},
-		resource:        src.Resource,
-		resourceVersion: resourceVersion,
-		namespace:       src.Namespace,
-		name:            src.Name,
-		keySpaceSize:    src.KeySpaceSize,
-		patchType:       patchType,
-		body:            []byte(src.Body),
-		maxRetries:      maxRetries,
+		resource:     src.Resource,
+		namespace:    src.Namespace,
+		name:         src.Name,
+		keySpaceSize: src.KeySpaceSize,
+		valueSize:    src.ValueSize,
+		maxRetries:   maxRetries,
 	}
 }
 
@@ -413,11 +407,23 @@ func (b *requestPatchBuilder) Build(cli rest.Interface) Requester {
 	finalName := fmt.Sprintf("%s-%d", b.name, suffix)
 	comps = append(comps, b.resource, finalName)
 
+	var body []byte
+
+	// For configmapas and secrets: generate data based on valueSize
+	if b.resource == "configmaps" || b.resource == "secrets" && b.valueSize > 0 {
+		randomData, _ := utils.RandString(b.valueSize)
+
+		body = []byte(fmt.Sprintf(`{"data":{"data-key":"%s"}}`, randomData))
+	} else {
+		// For other resources: patch based on simple data annotations
+		body = []byte(fmt.Sprintf(`{"metadata":{"annotations":{"force-update":"%d-%d"}}}`, suffix, time.Now().UnixNano()))
+	}
+
 	return &DiscardRequester{
 		BaseRequester: BaseRequester{
 			method: "PATCH",
-			req: cli.Patch(b.patchType).AbsPath(comps...).
-				Body(b.body).
+			req: cli.Patch(apitypes.MergePatchType).AbsPath(comps...).
+				Body(body).
 				MaxRetries(b.maxRetries),
 		},
 	}