diff --git a/devtools/server/actors/perf.js b/devtools/server/actors/perf.js
index 76a5eafddbe4..60b565c287ba 100644
--- a/devtools/server/actors/perf.js
+++ b/devtools/server/actors/perf.js
@@ -45,7 +45,7 @@ exports.PerfActor = ActorClassWithSpec(perfSpec, {
     Actor.prototype.destroy.call(this);
   },
 
-  startProfiler() {
+  startProfiler(options) {
     if (!IS_SUPPORTED_PLATFORM) {
       return false;
     }
@@ -53,10 +53,10 @@ exports.PerfActor = ActorClassWithSpec(perfSpec, {
     // For a quick implementation, decide on some default values. These may need
     // to be tweaked or made configurable as needed.
     const settings = {
-      entries: 1000000,
-      interval: 1,
-      features: ["js", "stackwalk", "threads", "leaf"],
-      threads: ["GeckoMain", "Compositor"]
+      entries: options.entries || 1000000,
+      interval: options.interval || 1,
+      features: options.features || ["js", "stackwalk", "threads", "leaf"],
+      threads: options.threads || ["GeckoMain", "Compositor"]
     };
 
     try {
@@ -141,6 +141,9 @@ exports.PerfActor = ActorClassWithSpec(perfSpec, {
         this.emit("profile-unlocked-from-private-browsing");
         break;
       case "profiler-started":
+        let param = subject.QueryInterface(Ci.nsIProfilerStartParams);
+        this.emit(topic, param.entries, param.interval, param.features);
+        break;
       case "profiler-stopped":
         this.emit(topic);
         break;
diff --git a/devtools/shared/specs/perf.js b/devtools/shared/specs/perf.js
index f60904dd6397..d82a4012dfac 100644
--- a/devtools/shared/specs/perf.js
+++ b/devtools/shared/specs/perf.js
@@ -3,14 +3,17 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 "use strict";
 
-const { RetVal, generateActorSpec } = require("devtools/shared/protocol");
+const { Arg, Option, RetVal, generateActorSpec } = require("devtools/shared/protocol");
 
 const perfDescription = {
   typeName: "perf",
 
   events: {
     "profiler-started": {
-      type: "profiler-started"
+      type: "profiler-started",
+      entries: Arg(0, "number"),
+      interval: Arg(1, "number"),
+      features: Arg(2, "number"),
     },
     "profiler-stopped": {
       type: "profiler-stopped"
@@ -25,7 +28,12 @@ const perfDescription = {
 
   methods: {
     startProfiler: {
-      request: {},
+      request: {
+        entries: Option(0, "number"),
+        interval: Option(0, "number"),
+        features: Option(0, "array:string"),
+        threads: Option(0, "array:string"),
+      },
       response: { value: RetVal("boolean") }
     },