diff --git a/system-test/busybench-js/src/busybench.js b/system-test/busybench-js/src/busybench.js
index e904957d..f60ba54a 100644
--- a/system-test/busybench-js/src/busybench.js
+++ b/system-test/busybench-js/src/busybench.js
@@ -25,9 +25,11 @@ const testArr = [];
  * It continues to do this until durationSeconds after the startTime.
  */
 function busyLoop(durationSeconds) {
+  const noop = () => {};
   for (let i = 0; i < testArr.length; i++) {
     for (let j = 0; j < testArr[i].length; j++) {
       testArr[i][j] = Math.sqrt(j * testArr[i][j]);
+      noop();
     }
   }
   if (Date.now() - startTime < 1000 * durationSeconds) {
diff --git a/system-test/busybench/src/busybench.ts b/system-test/busybench/src/busybench.ts
index feb7c828..c6690d45 100644
--- a/system-test/busybench/src/busybench.ts
+++ b/system-test/busybench/src/busybench.ts
@@ -27,9 +27,11 @@ const testArr: number[][] = [];
  * It continues to do this until durationSeconds after the startTime.
  */
 function busyLoop(durationSeconds: number) {
+  const noop = () => {};
   for (let i = 0; i < testArr.length; i++) {
     for (let j = 0; j < testArr[i].length; j++) {
       testArr[i][j] = Math.sqrt(j * testArr[i][j]);
+      noop();
     }
   }
   if (Date.now() - startTime < 1000 * durationSeconds) {
diff --git a/system-test/test.sh b/system-test/test.sh
index 9c632f32..dc7aaedd 100755
--- a/system-test/test.sh
+++ b/system-test/test.sh
@@ -57,10 +57,12 @@ fi
 
 node -v
 node --trace-warnings "$BENCHPATH" 10 $VERIFY_TIME_LINE_NUMBERS
+cp time.pb.gz /src/$(node -v)-time.pb.gz
+cp heap.pb.gz /src/$(node -v)-heap.pb.gz
 
 if [[ "$VERIFY_TIME_LINE_NUMBERS" == "true" ]]; then
   pprof -lines -top -nodecount=2 time.pb.gz | tee $tty | \
-      grep "busyLoop.*src/busybench.js:[2-3][08-9]"
+      grep "busyLoop.*src/busybench.js:[2-3][0-9]"
   pprof -filefunctions -top -nodecount=2 heap.pb.gz | tee $tty | \
       grep "busyLoop.*src/busybench.js"
 else