perf(producer): worker sizing measures screenshot capture, one browser launch fewer (#6630)

packages/producer/src/services/renderOrchestrator.test.ts

@@ -55,6 +55,7 @@ import {
   resolveAdaptersUsed,
   resolveDeShortBand,
   shouldClampDefaultDrawElement,
+  calibrationCaptureConfig,
   shouldPreferParallelDrawElement,
   shouldPreferSingleWorkerDrawElement,
   isCaptureParallelStreamRouterEnabled,
@@ -3638,6 +3639,22 @@ describe("shouldStreamParallelCapture (non-DE parallel streaming router)", () =>
   });
 });
 
+describe("calibrationCaptureConfig", () => {
+  const drawElementCfg = () => ({ ...createConfig(), useDrawElement: true });
+
+  it("measures screenshot capture, the mode parallel workers use", () => {
+    const cfg = drawElementCfg();
+    expect(calibrationCaptureConfig(cfg, {}).useDrawElement).toBe(false);
+    expect(cfg.useDrawElement).toBe(true);
+  });
+
+  it("keeps drawElement when parallel drawElement was opted into", () => {
+    const cfg = drawElementCfg();
+    expect(calibrationCaptureConfig(cfg, { PRODUCER_EXPERIMENTAL_FAST_CAPTURE: "true" })).toBe(cfg);
+    expect(calibrationCaptureConfig(cfg, { HF_DE_PARALLEL_STREAM: "true" })).toBe(cfg);
+  });
+});
+
 describe("shouldClampDefaultDrawElement (default-on drawElement clamp)", () => {
   const unverifiedParallel = {
     useDrawElement: true,

packages/producer/src/services/renderOrchestrator.ts

@@ -2842,6 +2842,24 @@ export function shouldClampDefaultDrawElement(args: {
   );
 }
 
+/**
+ * Calibration sizes a parallel render, and parallel workers capture by screenshot
+ * unless drawElement was opted into: measure that mode, without a drawElement init.
+ */
+export function calibrationCaptureConfig(
+  cfg: EngineConfig,
+  env: NodeJS.ProcessEnv = process.env,
+): EngineConfig {
+  const parallelKeepsDrawElement = !shouldClampDefaultDrawElement({
+    useDrawElement: cfg.useDrawElement,
+    fastCaptureExplicitOptIn: env.PRODUCER_EXPERIMENTAL_FAST_CAPTURE === "true",
+    useStreamingEncode: true,
+    workerCount: 2,
+    deParallelStreamVerified: env.HF_DE_PARALLEL_STREAM === "true",
+  });
+  return parallelKeepsDrawElement ? cfg : { ...cfg, useDrawElement: false };
+}
+
 export function resolveCaptureForceScreenshotForPageSideCompositing(args: {
   forceScreenshot: boolean;
   usePageSideCompositing: boolean;
@@ -4011,7 +4029,7 @@ async function executeRenderPipeline(input: {
         }),
         () =>
           runCaptureCalibration({
-            cfg,
+            cfg: calibrationCaptureConfig(cfg),
             fileServer: activeFileServer,
             workDir,
             log,