diff --git a/rust/otap-dataflow/crates/otap/src/batch_processor.rs b/rust/otap-dataflow/crates/otap/src/batch_processor.rs
index 3980c61c73..a0bc8ef5c3 100644
--- a/rust/otap-dataflow/crates/otap/src/batch_processor.rs
+++ b/rust/otap-dataflow/crates/otap/src/batch_processor.rs
@@ -196,7 +196,7 @@ const fn default_otap_max_size_items() -> Option<NonZeroUsize> {
 }
 
 const fn default_otap_sizer_items() -> Sizer {
-    Sizer::Bytes
+    Sizer::Items
 }
 
 const fn default_otlp_min_size_bytes() -> Option<NonZeroUsize> {
diff --git a/tools/pipeline_perf_test/test_suites/integration/continuous/passthrough.yaml b/tools/pipeline_perf_test/test_suites/integration/continuous/passthrough.yaml
index 4a94ddcc4f..4b7d701713 100644
--- a/tools/pipeline_perf_test/test_suites/integration/continuous/passthrough.yaml
+++ b/tools/pipeline_perf_test/test_suites/integration/continuous/passthrough.yaml
@@ -77,3 +77,15 @@ tests:
         observation_interval: 60
         signals_per_second: null
         max_batch_size: 512
+
+  - name: OTLP-BATCH-OTLP
+    from_template:
+      path: test_suites/integration/templates/test_steps/df-loadgen-steps-docker.yaml
+      variables:
+        result_dir: continuous_passthrough_batch
+        engine_config_template: test_suites/integration/templates/configs/engine/batch/otlp-batch-otlp.yaml
+        loadgen_exporter_type: otlp
+        backend_receiver_type: otlp
+        observation_interval: 60
+        signals_per_second: null
+        max_batch_size: 512
diff --git a/tools/pipeline_perf_test/test_suites/integration/templates/configs/engine/batch/otlp-batch-otlp.yaml b/tools/pipeline_perf_test/test_suites/integration/templates/configs/engine/batch/otlp-batch-otlp.yaml
new file mode 100644
index 0000000000..022faf17de
--- /dev/null
+++ b/tools/pipeline_perf_test/test_suites/integration/templates/configs/engine/batch/otlp-batch-otlp.yaml
@@ -0,0 +1,42 @@
+version: otel_dataflow/v1
+policies:
+  channel_capacity:
+    control:
+      node: 100
+      pipeline: 100
+    pdata: 100
+engine:
+  telemetry:
+    logs:
+      level: info
+groups:
+  default:
+    pipelines:
+      main:
+        nodes:
+          receiver:
+            type: urn:otel:receiver:otlp
+            config:
+              protocols:
+                grpc:
+                  listening_addr: 0.0.0.0:4317
+                  request_compression: gzip
+                  wait_for_result: true
+          batch:
+            type: urn:otel:processor:batch
+            config:
+              otlp:
+                min_size: 8192
+                sizer: bytes
+              flush_timeout: 200ms
+              format: preserve
+          exporter:
+            type: urn:otel:exporter:otlp_grpc
+            config:
+              grpc_endpoint: http://{{backend_hostname}}:1235
+              compression_method: gzip
+        connections:
+        - from: receiver
+          to: batch
+        - from: batch
+          to: exporter