From 1676c96e56f23083308629064b7b66c44535068e Mon Sep 17 00:00:00 2001
From: Camillo Bruni <cbruni@chromium.org>
Date: Mon, 15 Jun 2026 13:27:02 +0200
Subject: [PATCH 1/2] initial-implementation

---
 resources/developer-mode.mjs | 10 ++++++++++
 resources/shared/params.mjs  |  6 ++++++
 resources/suite-runner.mjs   | 13 +++++++++++++
 3 files changed, 29 insertions(+)

diff --git a/resources/developer-mode.mjs b/resources/developer-mode.mjs
index fdd254775..9b67d1e7e 100644
--- a/resources/developer-mode.mjs
+++ b/resources/developer-mode.mjs
@@ -23,7 +23,9 @@ export function createDeveloperModeContainer() {
     settings.append(createUIForMeasurePrepare());
     settings.append(createUIForWarmupSuite());
     settings.append(createUIForWarmupBeforeSync());
+    settings.append(createUIForWaitAfterSetup());
     settings.append(createUIForSyncStepDelay());
+    settings.append(createUIForWaitAfterSuite());
     settings.append(createUIForAsyncSteps());
     settings.append(createUIForLayoutMode());
 
@@ -89,6 +91,14 @@ function createUIForSyncStepDelay() {
     return createTimeRangeUI("Sync step delay: ", "waitBeforeSync");
 }
 
+function createUIForWaitAfterSetup() {
+    return createTimeRangeUI("Post setup delay: ", "waitAfterSetup");
+}
+
+function createUIForWaitAfterSuite() {
+    return createTimeRangeUI("Post suite delay: ", "waitAfterSuite");
+}
+
 function createTimeRangeUI(labelText, paramKey, unit = "ms", min = 0, max = 1000) {
     const range = document.createElement("input");
     range.type = "range";
diff --git a/resources/shared/params.mjs b/resources/shared/params.mjs
index 520679d24..82306fd84 100644
--- a/resources/shared/params.mjs
+++ b/resources/shared/params.mjs
@@ -20,8 +20,12 @@ export class Params {
     // "timer": The classic (as in Speedometer 2.x) way using setTimeout
     // "raf":   Using rAF callbacks, both for triggering the sync part and for measuring async time.
     measurementMethod = "raf";
+    // Wait time after suite preparation in ms.
+    waitAfterSetup = 0;
     // Wait time before the sync step in ms.
     waitBeforeSync = 0;
+    // Wait after running a suite.
+    waitAfterSuite = 0;
     // Warmup time before the sync step in ms.
     warmupBeforeSync = 0;
     // Seed for shuffling the execution order of suites.
@@ -61,7 +65,9 @@ export class Params {
         this.developerMode = this._parseBooleanParam(searchParams, "developerMode");
         this.useWarmupSuite = this._parseBooleanParam(searchParams, "useWarmupSuite");
         this.useAsyncSteps = this._parseBooleanParam(searchParams, "useAsyncSteps");
+        this.waitAfterSetup = this._parseIntParam(searchParams, "waitAfterSetup", 0);
         this.waitBeforeSync = this._parseIntParam(searchParams, "waitBeforeSync", 0);
+        this.waitAfterSuite = this._parseIntParam(searchParams, "waitAfterSuite", 0);
         this.warmupBeforeSync = this._parseIntParam(searchParams, "warmupBeforeSync", 0);
         this.measurementMethod = this._parseEnumParam(searchParams, "measurementMethod", ["raf"]);
         this.shuffleSeed = this._parseShuffleSeed(searchParams);
diff --git a/resources/suite-runner.mjs b/resources/suite-runner.mjs
index bb37318b0..1a8cb11a8 100644
--- a/resources/suite-runner.mjs
+++ b/resources/suite-runner.mjs
@@ -1,6 +1,11 @@
 import { STEP_RUNNER_LOOKUP } from "./shared/step-runner.mjs";
 import { WarmupSuite } from "./benchmark-runner.mjs";
 
+function delay(ms) {
+    if (ms > 0)
+        return new Promise((resolve) => setTimeout(resolve, ms));
+}
+
 export class SuiteRunner {
     #frame;
     #page;
@@ -72,6 +77,8 @@ export class SuiteRunner {
         const suiteStartLabel = `suite-${suiteName}-start`;
         const suiteEndLabel = `suite-${suiteName}-end`;
 
+        await delay(this.#params.waitAfterSetup);
+
         performance.mark(suiteStartLabel);
         for (const step of this.#suite.tests) {
             if (this.#client?.willRunTest)
@@ -84,6 +91,8 @@ export class SuiteRunner {
         }
         performance.mark(suiteEndLabel);
 
+        await delay(this.#params.waitAfterSuite);
+
         performance.measure(`suite-${suiteName}`, suiteStartLabel, suiteEndLabel);
         this._validateSuiteResults();
         await this._updateClient();
@@ -178,11 +187,15 @@ export class RemoteSuiteRunner extends SuiteRunner {
     }
 
     async _runSuite() {
+        await delay(this.params.waitAfterSetup);
+
         // Ask workload to run its own tests.
         this.frame.contentWindow.postMessage({ id: this.appId, key: "benchmark-connector", type: "benchmark-suite", name: this.suite.config?.name || "default" }, "*");
         // Capture metrics from the completed tests.
         const response = await this._subscribeOnce("suite-complete");
 
+        await delay(this.params.waitAfterSuite);
+
         this.suiteResults.tests = {
             ...this.suiteResults.tests,
             ...response.result.tests,

From a1826dbb21a5fe1181611988ae404f8196fe238a Mon Sep 17 00:00:00 2001
From: Camillo Bruni <cbruni@chromium.org>
Date: Mon, 15 Jun 2026 13:27:44 +0200
Subject: [PATCH 2/2] cleanup

---
 resources/suite-runner.mjs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/resources/suite-runner.mjs b/resources/suite-runner.mjs
index 1a8cb11a8..83bd3dd31 100644
--- a/resources/suite-runner.mjs
+++ b/resources/suite-runner.mjs
@@ -4,6 +4,7 @@ import { WarmupSuite } from "./benchmark-runner.mjs";
 function delay(ms) {
     if (ms > 0)
         return new Promise((resolve) => setTimeout(resolve, ms));
+    return undefined;
 }
 
 export class SuiteRunner {