From f9f5b01cc23f3084f83ccf15c144de130b8b3222 Mon Sep 17 00:00:00 2001
From: Lauri Kasanen <cand@gmx.com>
Date: Tue, 27 Jul 2021 15:28:02 +0300
Subject: [PATCH] Initial frame stat tracking

---
 core/display.js | 13 +++++++++++++
 core/rfb.js     | 39 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+)

diff --git a/core/display.js b/core/display.js
index 30fa2891..dd14a6a2 100644
--- a/core/display.js
+++ b/core/display.js
@@ -21,6 +21,8 @@ export default class Display {
         this._fbWidth = 0;
         this._fbHeight = 0;
 
+        this._renderMs = 0;
+
         this._prevDrawStyle = "";
 
         Log.Debug(">> Display.constructor");
@@ -91,6 +93,13 @@ export default class Display {
         return this._fbHeight;
     }
 
+    get renderMs() {
+        return this._renderMs;
+    }
+    set renderMs(val) {
+        this._renderMs = val;
+    }
+
     // ===== PUBLIC METHODS =====
 
     viewportChangePos(deltaX, deltaY) {
@@ -470,6 +479,7 @@ export default class Display {
 
     _scanRenderQ() {
         let ready = true;
+        let before = Date.now();
         while (ready && this._renderQ.length > 0) {
             const a = this._renderQ[0];
             switch (a.type) {
@@ -513,5 +523,8 @@ export default class Display {
             this._flushing = false;
             this.onflush();
         }
+
+        let elapsed = Date.now() - before;
+        this._renderMs += elapsed;
     }
 }
diff --git a/core/rfb.js b/core/rfb.js
index db774e12..74d97dc7 100644
--- a/core/rfb.js
+++ b/core/rfb.js
@@ -142,6 +142,8 @@ export default class RFB extends EventTargetMixin {
         this._maxVideoResolutionX = 960;
         this._maxVideoResolutionY = 540;
 
+        this._trackFrameStats = false;
+
         this._clipboardText = null;
         this._clipboardServerCapabilitiesActions = {};
         this._clipboardServerCapabilitiesFormats = {};
@@ -2250,11 +2252,18 @@ export default class RFB extends EventTargetMixin {
         let first, ret;
         switch (msgType) {
             case 0:  // FramebufferUpdate
+                let before = Date.now();
+                this._display.renderMs = 0;
                 ret = this._framebufferUpdate();
                 if (ret && !this._enabledContinuousUpdates) {
                     RFB.messages.fbUpdateRequest(this._sock, true, 0, 0,
                                                  this._fbWidth, this._fbHeight);
                 }
+                let elapsed = Date.now() - before;
+                if (this._trackFrameStats) {
+                    RFB.messages.sendFrameStats(this._sock, elapsed, this._display.renderMs);
+                    this._trackFrameStats = false;
+                }
                 return ret;
 
             case 1:  // SetColorMapEntries
@@ -2287,6 +2296,10 @@ export default class RFB extends EventTargetMixin {
             case 178: // KASM bottleneck stats
                 return this._handle_server_stats_msg();
 
+            case 179: // KASM requesting frame stats
+                this._trackFrameStats = true;
+                return true;
+
             case 248: // ServerFence
                 return this._handleServerFenceMsg();
 
@@ -3035,6 +3048,32 @@ RFB.messages = {
         sock.flush();
     },
 
+    sendFrameStats(sock, allMs, renderMs) {
+        const buff = sock._sQ;
+        const offset = sock._sQlen;
+
+	if (buff == null) { return; }
+
+        buff[offset] = 179; // msg-type
+
+        buff[offset + 1] = 0; // padding
+        buff[offset + 2] = 0; // padding
+        buff[offset + 3] = 0; // padding
+
+        buff[offset + 4] = allMs >> 24;
+        buff[offset + 5] = allMs >> 16;
+        buff[offset + 6] = allMs >> 8;
+        buff[offset + 7] = allMs;
+
+        buff[offset + 8] = renderMs >> 24;
+        buff[offset + 9] = renderMs >> 16;
+        buff[offset + 10] = renderMs >> 8;
+        buff[offset + 11] = renderMs;
+
+        sock._sQlen += 12;
+        sock.flush();
+    },
+
 
     enableContinuousUpdates(sock, enable, x, y, width, height) {
         const buff = sock._sQ;