feat: Playwright improvements (#3495)

Author: hassy

examples/browser-load-testing-playwright/browser-load-test.ts

@@ -13,6 +13,14 @@ export const config = {
   }
 };
 
+export const before = {
+  engine: 'playwright',
+  testFunction: async function beforeFunctionHook(_page, userContext, _events) {
+    // Any scenario variables we add via userContext.vars in this before hook will be available in every VU
+    userContext.vars.testStartTime = new Date();
+  }
+};
+
 export const scenarios = [
   {
     engine: 'playwright',

packages/artillery/lib/platform/local/index.js

@@ -30,7 +30,10 @@ class PlatformLocal {
     await this.init();
 
     if (this.platformOpts.mode === 'distribute') {
-      const count = Math.max(1, os.cpus().length - 1);
+      // Disable worker threads for Playwright-based load tests
+      const count = this.script.config.engines?.playwright
+        ? 1
+        : Math.max(1, os.cpus().length - 1);
       this.workerScripts = divideWork(this.script, count);
       this.count = this.workerScripts.length;
     } else {