diff --git a/package-lock.json b/package-lock.json
index 7a3032464dd..544c02792fa 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -13,6 +13,7 @@
"@divmode/rrweb-plugin-console-record": "^0.0.40",
"@hapi/bourne": "^3.0.0",
"@hapi/hoek": "^11.0.4",
+ "@pyroscope/nodejs": "^0.4.10",
"better-sqlite3": "^11.10.0",
"debug": "^4.4.1",
"del": "^8.0.1",
@@ -509,6 +510,32 @@
"@jridgewell/sourcemap-codec": "^1.4.10"
}
},
+ "node_modules/@datadog/pprof": {
+ "version": "5.13.3",
+ "resolved": "https://registry.npmjs.org/@datadog/pprof/-/pprof-5.13.3.tgz",
+ "integrity": "sha512-G25IicP7pc5CXmAfVz7nrIERsKK9hvPz6p7xsLTUwG4Qs+Zgd5KFedKCVsnvNasLc7l7OXQ6839ajowgQLWTyw==",
+ "hasInstallScript": true,
+ "license": "Apache-2.0",
+ "dependencies": {
+ "delay": "^5.0.0",
+ "node-gyp-build": "<4.0",
+ "p-limit": "^3.1.0",
+ "pprof-format": "^2.2.1",
+ "source-map": "^0.7.4"
+ },
+ "engines": {
+ "node": ">=16"
+ }
+ },
+ "node_modules/@datadog/pprof/node_modules/source-map": {
+ "version": "0.7.6",
+ "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.7.6.tgz",
+ "integrity": "sha512-i5uvt8C3ikiWeNZSVZNWcfZPItFQOsYTUAOkcUPGd8DqDy1uOUikjt5dG+uRlwyvR108Fb9DOd4GvXfT0N2/uQ==",
+ "license": "BSD-3-Clause",
+ "engines": {
+ "node": ">= 12"
+ }
+ },
"node_modules/@divmode/rrdom": {
"version": "0.0.40",
"resolved": "https://registry.npmjs.org/@divmode/rrdom/-/rrdom-0.0.40.tgz",
@@ -2213,6 +2240,70 @@
"node": ">=18"
}
},
+ "node_modules/@pyroscope/nodejs": {
+ "version": "0.4.10",
+ "resolved": "https://registry.npmjs.org/@pyroscope/nodejs/-/nodejs-0.4.10.tgz",
+ "integrity": "sha512-MhRT1O4CeKQo5Zqbl64wQS+EyyrKG5oToFj0+fH+YZHcjEFEdEgqSZb22HMkbwXKTr6HvIbSdwoHd3BpVl96bA==",
+ "license": "Apache-2.0",
+ "dependencies": {
+ "@datadog/pprof": "5.13.3",
+ "debug": "^4.4.3",
+ "p-limit": "^7.3.0",
+ "regenerator-runtime": "^0.14.1",
+ "source-map": "^0.7.6"
+ },
+ "engines": {
+ "node": ">=20"
+ },
+ "peerDependencies": {
+ "express": "^4.0.0 || ^5.0.0",
+ "fastify": "^5.7.3"
+ },
+ "peerDependenciesMeta": {
+ "express": {
+ "optional": true
+ },
+ "fastify": {
+ "optional": true
+ }
+ }
+ },
+ "node_modules/@pyroscope/nodejs/node_modules/p-limit": {
+ "version": "7.3.0",
+ "resolved": "https://registry.npmjs.org/p-limit/-/p-limit-7.3.0.tgz",
+ "integrity": "sha512-7cIXg/Z0M5WZRblrsOla88S4wAK+zOQQWeBYfV3qJuJXMr+LnbYjaadrFaS0JILfEDPVqHyKnZ1Z/1d6J9VVUw==",
+ "license": "MIT",
+ "dependencies": {
+ "yocto-queue": "^1.2.1"
+ },
+ "engines": {
+ "node": ">=20"
+ },
+ "funding": {
+ "url": "https://github.com/sponsors/sindresorhus"
+ }
+ },
+ "node_modules/@pyroscope/nodejs/node_modules/source-map": {
+ "version": "0.7.6",
+ "resolved": "https://registry.npmjs.org/source-map/-/source-map-0.7.6.tgz",
+ "integrity": "sha512-i5uvt8C3ikiWeNZSVZNWcfZPItFQOsYTUAOkcUPGd8DqDy1uOUikjt5dG+uRlwyvR108Fb9DOd4GvXfT0N2/uQ==",
+ "license": "BSD-3-Clause",
+ "engines": {
+ "node": ">= 12"
+ }
+ },
+ "node_modules/@pyroscope/nodejs/node_modules/yocto-queue": {
+ "version": "1.2.2",
+ "resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-1.2.2.tgz",
+ "integrity": "sha512-4LCcse/U2MHZ63HAJVE+v71o7yOdIe4cZ70Wpf8D/IyjDKYQLV5GD46B+hSTjJsvV5PztjvHoU580EftxjDZFQ==",
+ "license": "MIT",
+ "engines": {
+ "node": ">=12.20"
+ },
+ "funding": {
+ "url": "https://github.com/sponsors/sindresorhus"
+ }
+ },
"node_modules/@rolldown/binding-android-arm64": {
"version": "1.0.0-rc.9",
"resolved": "https://registry.npmjs.org/@rolldown/binding-android-arm64/-/binding-android-arm64-1.0.0-rc.9.tgz",
@@ -4439,6 +4530,18 @@
"url": "https://github.com/sponsors/sindresorhus"
}
},
+ "node_modules/delay": {
+ "version": "5.0.0",
+ "resolved": "https://registry.npmjs.org/delay/-/delay-5.0.0.tgz",
+ "integrity": "sha512-ReEBKkIfe4ya47wlPYf/gu5ib6yUG0/Aez0JQZQz94kiWtRQvZIQbTiehsnwHvLSWJnQdhVeqYue7Id1dKr0qw==",
+ "license": "MIT",
+ "engines": {
+ "node": ">=10"
+ },
+ "funding": {
+ "url": "https://github.com/sponsors/sindresorhus"
+ }
+ },
"node_modules/detect-libc": {
"version": "2.1.2",
"resolved": "https://registry.npmjs.org/detect-libc/-/detect-libc-2.1.2.tgz",
@@ -7423,6 +7526,17 @@
"node": ">=6.0.0"
}
},
+ "node_modules/node-gyp-build": {
+ "version": "3.9.0",
+ "resolved": "https://registry.npmjs.org/node-gyp-build/-/node-gyp-build-3.9.0.tgz",
+ "integrity": "sha512-zLcTg6P4AbcHPq465ZMFNXx7XpKKJh+7kkN699NiQWisR2uWYOWNWqRHAmbnmKiL4e9aLSlmy5U7rEMUXV59+A==",
+ "license": "MIT",
+ "bin": {
+ "node-gyp-build": "bin.js",
+ "node-gyp-build-optional": "optional.js",
+ "node-gyp-build-test": "build-test.js"
+ }
+ },
"node_modules/node-gyp-build-optional-packages": {
"version": "5.2.2",
"resolved": "https://registry.npmjs.org/node-gyp-build-optional-packages/-/node-gyp-build-optional-packages-5.2.2.tgz",
@@ -7546,7 +7660,6 @@
"resolved": "https://registry.npmjs.org/p-limit/-/p-limit-3.1.0.tgz",
"integrity": "sha512-TYOanM3wGwNGsZN2cVTYPArw454xnXj5qmWF1bEoAc4+cU/ol7GVh7odevjp1FNHduHc3KZMcFduxU5Xc6uJRQ==",
"license": "MIT",
- "optional": true,
"dependencies": {
"yocto-queue": "^0.1.0"
},
@@ -7988,6 +8101,12 @@
"node": ">=0.10.0"
}
},
+ "node_modules/pprof-format": {
+ "version": "2.2.1",
+ "resolved": "https://registry.npmjs.org/pprof-format/-/pprof-format-2.2.1.tgz",
+ "integrity": "sha512-p4tVN7iK19ccDqQv8heyobzUmbHyds4N2FI6aBMcXz6y99MglTWDxIyhFkNaLeEXs6IFUEzT0zya0icbSLLY0g==",
+ "license": "MIT"
+ },
"node_modules/prebuild-install": {
"version": "7.1.3",
"resolved": "https://registry.npmjs.org/prebuild-install/-/prebuild-install-7.1.3.tgz",
@@ -8487,6 +8606,12 @@
"url": "https://paulmillr.com/funding/"
}
},
+ "node_modules/regenerator-runtime": {
+ "version": "0.14.1",
+ "resolved": "https://registry.npmjs.org/regenerator-runtime/-/regenerator-runtime-0.14.1.tgz",
+ "integrity": "sha512-dYnhHh0nJoMfnkZs6GmmhFknAGRrLznOu5nc9ML+EJxGvrx6H7teuevqVqCuPcPK//3eDrrjQhehXVx9cnkGdw==",
+ "license": "MIT"
+ },
"node_modules/require-directory": {
"version": "2.1.1",
"resolved": "https://registry.npmjs.org/require-directory/-/require-directory-2.1.1.tgz",
@@ -10358,7 +10483,6 @@
"resolved": "https://registry.npmjs.org/yocto-queue/-/yocto-queue-0.1.0.tgz",
"integrity": "sha512-rVksvsnNCdJ/ohGc6xgPwyN8eheCxsiLM8mxuE/t/mOVqJewPuO1miLpTHQiRgTKCLexL4MeAFVagts7HmNZ2Q==",
"license": "MIT",
- "optional": true,
"engines": {
"node": ">=10"
},
diff --git a/package.json b/package.json
index 3e8d50db825..11cb8809853 100644
--- a/package.json
+++ b/package.json
@@ -62,6 +62,7 @@
"@divmode/rrweb-plugin-console-record": "^0.0.40",
"@hapi/bourne": "^3.0.0",
"@hapi/hoek": "^11.0.4",
+ "@pyroscope/nodejs": "^0.4.10",
"better-sqlite3": "^11.10.0",
"debug": "^4.4.1",
"del": "^8.0.1",
diff --git a/src/index.ts b/src/index.ts
index 837f511d19a..7852f63bb37 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -1,6 +1,25 @@
+import Pyroscope from '@pyroscope/nodejs';
import { Browserless } from '@browserless.io/browserless';
import { Effect } from 'effect';
+// ── Continuous profiling (Pyroscope) ─────────────────────────────────
+// Must init before any other code to capture full startup profile.
+// Gracefully skips when PYROSCOPE_SERVER_ADDRESS is unset (local dev).
+if (process.env.PYROSCOPE_SERVER_ADDRESS) {
+ Pyroscope.init({
+ serverAddress: process.env.PYROSCOPE_SERVER_ADDRESS,
+ appName: process.env.OTEL_SERVICE_NAME ?? 'browserless',
+ basicAuthUser: process.env.PYROSCOPE_BASIC_AUTH_USER ?? '',
+ basicAuthPassword: process.env.PYROSCOPE_BASIC_AUTH_PASSWORD ?? '',
+ wall: { collectCpuTime: true },
+ tags: {
+ env: process.env.OTEL_DEPLOYMENT_ENVIRONMENT ?? 'production',
+ server: 'flatcar',
+ },
+ });
+ Pyroscope.start();
+}
+
// ── Fail-fast env validation ─────────────────────────────────────────
// REQUIRED env vars must be present BEFORE the server accepts connections.
// Without this, a stale `node --watch` process (started without proper env)
diff --git a/src/session/cloudflare-solver.ts b/src/session/cloudflare-solver.ts
index 4e547599baf..540b6173f16 100644
--- a/src/session/cloudflare-solver.ts
+++ b/src/session/cloudflare-solver.ts
@@ -1,4 +1,4 @@
-import { Cause, Effect, Exit, FiberMap, Layer, ManagedRuntime, Scope, type Tracer } from 'effect';
+import { Cause, Effect, Exit, FiberMap, Layer, ManagedRuntime, Scope, Semaphore, type Tracer } from 'effect';
import { CdpSessionId } from '../shared/cloudflare-detection.js';
import type { TargetId, CloudflareConfig } from '../shared/cloudflare-detection.js';
import { CloudflareDetector } from './cf/cloudflare-detector.js';
@@ -150,13 +150,20 @@ export class CloudflareSolver {
const proxyOrDirect: SendCommand = (...args) => (self.sendViaProxy || sendCommand)(...args);
- const cdpSenderLayer = Layer.succeed(CdpSender, CdpSender.of({
- send: (method, params, sessionId, timeoutMs) =>
- liftSend(sendCommand, method, params, sessionId, timeoutMs),
- sendViaProxy: (method, params, sessionId, timeoutMs) =>
- liftSend(proxyOrDirect, method, params, sessionId, timeoutMs),
- sendViaBrowser: (method, params, sessionId, timeoutMs) =>
- liftSend(proxyOrDirect, method, params, sessionId, timeoutMs),
+ // Semaphore limits concurrent CDP commands to Chrome — prevents backpressure
+ // when multiple tabs have active detection/solve loops firing simultaneously.
+ const CDP_CONCURRENCY = 3;
+ const cdpSenderLayer = Layer.effect(CdpSender, Effect.gen(function*() {
+ const sem = yield* Semaphore.make(CDP_CONCURRENCY);
+ const throttle = (effect: Effect.Effect) => sem.withPermits(1)(effect);
+ return CdpSender.of({
+ send: (method, params, sessionId, timeoutMs) =>
+ throttle(liftSend(sendCommand, method, params, sessionId, timeoutMs)),
+ sendViaProxy: (method, params, sessionId, timeoutMs) =>
+ throttle(liftSend(proxyOrDirect, method, params, sessionId, timeoutMs)),
+ sendViaBrowser: (method, params, sessionId, timeoutMs) =>
+ throttle(liftSend(proxyOrDirect, method, params, sessionId, timeoutMs)),
+ });
}));
const solverEventsLayer = Layer.succeed(SolverEvents, SolverEvents.of({
@@ -196,8 +203,8 @@ export class CloudflareSolver {
}));
// SolveDispatcher — routes solve attempts through the Effect solver.
- // Per-solve isolated WS: each solve gets its own WebSocket to Chrome,
- // Each solve gets its own isolated WS connection, so no concurrency limit needed.
+ // Per-solve isolated WS: each solve gets its own WebSocket to Chrome.
+ // Browser-level sends (originalSender) inherit the Semaphore from cdpSenderLayer.
const solveDispatcherLayer = Layer.effect(SolveDispatcher, Effect.gen(function*() {
const solverEvents = yield* SolverEvents;
const solveDeps = yield* SolveDeps;
@@ -411,7 +418,7 @@ export class CloudflareSolver {
}
// FiberMap.run auto-interrupts existing fiber for same key.
- // The detection effect is wrapped in catchAllCause to prevent silent fiber
+ // The detection effect is wrapped in catchCause to prevent silent fiber
// death — without this, defects (NPE in emitClientEvent, etc.) kill the fiber
// and pydoll never receives cf.solved/cf.failed (the "events=1" failure mode).
const guarded = this.detector.detectTurnstileWidgetEffect(targetId, cdpSessionId).pipe(