diff --git a/packages/playwright-test/src/dispatcher.ts b/packages/playwright-test/src/dispatcher.ts
index fabbc1193a..f9296ec437 100644
--- a/packages/playwright-test/src/dispatcher.ts
+++ b/packages/playwright-test/src/dispatcher.ts
@@ -111,7 +111,7 @@ export class Dispatcher {
       worker = this._createWorker(job, index, this._loader.serialize());
       this._workerSlots[index].worker = worker;
       worker.on('exit', () => this._workerSlots[index].worker = undefined);
-      await worker.init();
+      await worker.start();
       if (this._isStopped) // Check stopped signal after async hop.
         return;
     }
diff --git a/packages/playwright-test/src/ipc.ts b/packages/playwright-test/src/ipc.ts
index f6ca17ba30..b2fce6f7ff 100644
--- a/packages/playwright-test/src/ipc.ts
+++ b/packages/playwright-test/src/ipc.ts
@@ -35,9 +35,9 @@ export type WorkerIsolation =
 
 
 export type ProcessInitParams = {
-  workerIndex?: number;
   stdoutParams: TtyParams;
   stderrParams: TtyParams;
+  processName: string;
 };
 
 export type WorkerInitParams = {
diff --git a/packages/playwright-test/src/process.ts b/packages/playwright-test/src/process.ts
index 100f7e935d..43c9710879 100644
--- a/packages/playwright-test/src/process.ts
+++ b/packages/playwright-test/src/process.ts
@@ -37,9 +37,7 @@ export type ProtocolResponse = {
 
 export class ProcessRunner {
   appendProcessTeardownDiagnostics(error: TestInfoError) { }
-  unhandledError(reason: any) { }
-  async cleanup(): Promise<void> { }
-  async stop(): Promise<void> { }
+  async gracefullyClose(): Promise<void> { }
 
   protected dispatchEvent(method: string, params: any) {
     const response: ProtocolResponse = { method, params };
@@ -74,29 +72,18 @@ process.on('SIGINT', () => {});
 process.on('SIGTERM', () => {});
 
 let processRunner: ProcessRunner;
-let workerIndex: number | undefined;
-
-process.on('unhandledRejection', (reason, promise) => {
-  if (processRunner)
-    processRunner.unhandledError(reason);
-});
-
-process.on('uncaughtException', error => {
-  if (processRunner)
-    processRunner.unhandledError(error);
-});
-
+let processName: string | undefined;
 process.on('message', async message => {
-  if (message.method === 'init') {
-    const initParams = message.params as ProcessInitParams;
-    workerIndex = initParams.workerIndex;
-    initConsoleParameters(initParams);
+  if (message.method === '__init__') {
+    const { processParams, runnerParams, runnerScript } = message.params as { processParams: ProcessInitParams, runnerParams: any, runnerScript: string };
+    setTtyParams(process.stdout, processParams.stdoutParams);
+    setTtyParams(process.stderr, processParams.stderrParams);
     startProfiling();
-    const { create } = require(process.env.PW_PROCESS_RUNNER_SCRIPT!);
-    processRunner = create(initParams) as ProcessRunner;
+    const { create } = require(runnerScript);
+    processRunner = create(runnerParams) as ProcessRunner;
     return;
   }
-  if (message.method === 'stop') {
+  if (message.method === '__stop__') {
     await gracefullyCloseAndExit();
     return;
   }
@@ -121,12 +108,10 @@ async function gracefullyCloseAndExit() {
   setTimeout(() => process.exit(0), 30000);
   // Meanwhile, try to gracefully shutdown.
   try {
-    if (processRunner) {
-      await processRunner.stop();
-      await processRunner.cleanup();
-    }
-    if (workerIndex !== undefined)
-      await stopProfiling(workerIndex);
+    if (processRunner)
+      await processRunner.gracefullyClose();
+    if (processName)
+      await stopProfiling(processName);
   } catch (e) {
     try {
       const error = serializeError(e);
@@ -155,12 +140,6 @@ function chunkToParams(chunk: Buffer | string):  { text?: string, buffer?: strin
   return { text: chunk };
 }
 
-function initConsoleParameters(initParams: ProcessInitParams) {
-  // Make sure the output supports colors.
-  setTtyParams(process.stdout, initParams.stdoutParams);
-  setTtyParams(process.stderr, initParams.stderrParams);
-}
-
 function setTtyParams(stream: WriteStream, params: TtyParams) {
   stream.isTTY = true;
   if (params.rows)
diff --git a/packages/playwright-test/src/processHost.ts b/packages/playwright-test/src/processHost.ts
index 51583efcb0..a752dc2d5a 100644
--- a/packages/playwright-test/src/processHost.ts
+++ b/packages/playwright-test/src/processHost.ts
@@ -33,13 +33,15 @@ export class ProcessHost<InitParams> extends EventEmitter {
   private _runnerScript: string;
   private _lastMessageId = 0;
   private _callbacks = new Map<number, { resolve: (result: any) => void, reject: (error: Error) => void }>();
+  private _processName: string;
 
-  constructor(runnerScript: string) {
+  constructor(runnerScript: string, processName: string) {
     super();
     this._runnerScript = runnerScript;
+    this._processName = processName;
   }
 
-  async doInit(params: InitParams) {
+  protected async startRunner(runnerParams: InitParams) {
     this.process = child_process.fork(require.resolve('./process'), {
       detached: false,
       env: {
@@ -90,9 +92,16 @@ export class ProcessHost<InitParams> extends EventEmitter {
         columns: process.stderr.columns,
         colorDepth: process.stderr.getColorDepth?.() || 8
       },
+      processName: this._processName
     };
 
-    this.send({ method: 'init', params: { ...processParams, ...params } });
+    this.send({
+      method: '__init__', params: {
+        processParams,
+        runnerScript: this._runnerScript,
+        runnerParams
+      }
+    });
   }
 
   protected sendMessage(message: { method: string, params?: any }) {
@@ -116,7 +125,7 @@ export class ProcessHost<InitParams> extends EventEmitter {
     if (this.didExit)
       return;
     if (!this._didSendStop) {
-      this.send({ method: 'stop' });
+      this.send({ method: '__stop__' });
       this._didSendStop = true;
     }
     await new Promise(f => this.once('exit', f));
diff --git a/packages/playwright-test/src/profiler.ts b/packages/playwright-test/src/profiler.ts
index 482da26461..b6344ad432 100644
--- a/packages/playwright-test/src/profiler.ts
+++ b/packages/playwright-test/src/profiler.ts
@@ -34,14 +34,14 @@ export async function startProfiling() {
   });
 }
 
-export async function stopProfiling(workerIndex: number | undefined) {
+export async function stopProfiling(processName: string | undefined) {
   if (!profileDir)
     return;
 
   await new Promise<void>(f => session.post('Profiler.stop', (err, { profile }) => {
     if (!err) {
       fs.mkdirSync(profileDir, { recursive: true });
-      fs.writeFileSync(path.join(profileDir, workerIndex === undefined ? 'runner.json' : 'worker' + workerIndex + '.json'), JSON.stringify(profile));
+      fs.writeFileSync(path.join(profileDir, (processName || 'runner') + '.json'), JSON.stringify(profile));
     }
     f();
   }));
diff --git a/packages/playwright-test/src/workerHost.ts b/packages/playwright-test/src/workerHost.ts
index 9a91baa222..c690720905 100644
--- a/packages/playwright-test/src/workerHost.ts
+++ b/packages/playwright-test/src/workerHost.ts
@@ -25,15 +25,16 @@ export class WorkerHost extends ProcessHost<WorkerInitParams> {
   readonly workerIndex: number;
   private _hash: string;
   currentTestId: string | null = null;
-  private _initParams: WorkerInitParams;
+  private _params: WorkerInitParams;
 
   constructor(testGroup: TestGroup, parallelIndex: number, workerIsolation: WorkerIsolation, loader: SerializedLoaderData) {
-    super(require.resolve('./workerRunner.js'));
-    this.workerIndex = lastWorkerIndex++;
+    const workerIndex = lastWorkerIndex++;
+    super(require.resolve('./workerRunner.js'), `worker-${workerIndex}`);
+    this.workerIndex = workerIndex;
     this.parallelIndex = parallelIndex;
     this._hash = testGroup.workerHash;
 
-    this._initParams = {
+    this._params = {
       workerIsolation,
       workerIndex: this.workerIndex,
       parallelIndex,
@@ -43,8 +44,8 @@ export class WorkerHost extends ProcessHost<WorkerInitParams> {
     };
   }
 
-  async init() {
-    await this.doInit(this._initParams);
+  async start() {
+    await this.startRunner(this._params);
   }
 
   runTestGroup(runPayload: RunPayload) {
diff --git a/packages/playwright-test/src/workerRunner.ts b/packages/playwright-test/src/workerRunner.ts
index 86facca1e4..8ae4fba87f 100644
--- a/packages/playwright-test/src/workerRunner.ts
+++ b/packages/playwright-test/src/workerRunner.ts
@@ -68,9 +68,12 @@ export class WorkerRunner extends ProcessRunner {
     // Resolve this promise, so worker does not stall waiting for the non-existent run to finish,
     // when it was sopped before running any test group.
     this._runFinished.resolve();
+
+    process.on('unhandledRejection', reason => this.unhandledError(reason));
+    process.on('uncaughtException', error => this.unhandledError(error));
   }
 
-  override stop(): Promise<void> {
+  private _stop(): Promise<void> {
     if (!this._isStopped) {
       this._isStopped = true;
 
@@ -83,7 +86,9 @@ export class WorkerRunner extends ProcessRunner {
     return this._runFinished;
   }
 
-  override async cleanup() {
+  override async gracefullyClose() {
+    await this._stop();
+
     // We have to load the project to get the right deadline below.
     await this._loadIfNeeded();
     await this._teardownScopes();
@@ -133,7 +138,7 @@ export class WorkerRunner extends ProcessRunner {
       this._fatalErrors.push(timeoutError);
   }
 
-  override unhandledError(error: Error | any) {
+  unhandledError(error: Error | any) {
     // Usually, we do not differentiate between errors in the control flow
     // and unhandled errors - both lead to the test failing. This is good for regular tests,
     // so that you can, e.g. expect() from inside an event handler. The test fails,
@@ -155,7 +160,7 @@ export class WorkerRunner extends ProcessRunner {
       if (!this._fatalErrors.length)
         this._fatalErrors.push(serializeError(error));
     }
-    this.stop();
+    this._stop();
   }
 
   private async _loadIfNeeded() {
@@ -208,7 +213,7 @@ export class WorkerRunner extends ProcessRunner {
         }
       } else {
         fatalUnknownTestIds = runPayload.entries.map(e => e.testId);
-        this.stop();
+        this._stop();
       }
     } catch (e) {
       // In theory, we should run above code without any errors.