From 08815fa938ba070b0756f37e1efda1b1f8abb0d7 Mon Sep 17 00:00:00 2001
From: Nataniel Borges <natanieljr@google.com>
Date: Wed, 9 Mar 2022 17:32:55 +0100
Subject: [PATCH] Freeze objects for performance

Frozen objects don't trigger Vue's reactive Observers and are significantly faster. With this changes, winscope can now load traces with over 100mb

Bug: 211049519
Test: build winscope and open a large trace
Change-Id: Iec9f91e408db734ce884cf846d5c2826ff346484
---
 tools/winscope/src/DataInput.vue            | 12 ++++++++++--
 tools/winscope/src/dumps/DumpBase.ts        |  4 ++--
 tools/winscope/src/main.js                  |  8 ++++++--
 tools/winscope/src/traces/SurfaceFlinger.ts |  8 ++++----
 tools/winscope/src/traces/TraceBase.ts      | 12 ++++++------
 5 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/tools/winscope/src/DataInput.vue b/tools/winscope/src/DataInput.vue
index 8cfa29b29..57fcb9810 100644
--- a/tools/winscope/src/DataInput.vue
+++ b/tools/winscope/src/DataInput.vue
@@ -356,8 +356,12 @@ export default {
         }
         decodedFileTypes.add(dataType);
 
+        const frozenData = Object.freeze(decodedFile.data.data);
+        delete decodedFile.data.data;
+        decodedFile.data.data = frozenData;
+
         this.$set(this.dataFiles,
-            dataType, decodedFile.data);
+            dataType, Object.freeze(decodedFile.data));
       }
 
       // TODO(b/169305853): Remove this once we have magic numbers or another
@@ -369,7 +373,11 @@ export default {
 
           const selectedFile =
               this.getMostLikelyCandidateFile(dataType, files);
-          this.$set(this.dataFiles, dataType, selectedFile);
+          const frozenData = Object.freeze(selectedFile.data);
+          delete selectedFile.data;
+          selectedFile.data = frozenData;
+
+          this.$set(this.dataFiles, dataType, Object.freeze(selectedFile));
 
           // Remove selected file from overriden list
           const index = files.indexOf(selectedFile);
diff --git a/tools/winscope/src/dumps/DumpBase.ts b/tools/winscope/src/dumps/DumpBase.ts
index 9e2bd141e..38c86c4d7 100644
--- a/tools/winscope/src/dumps/DumpBase.ts
+++ b/tools/winscope/src/dumps/DumpBase.ts
@@ -23,7 +23,7 @@ export default abstract class DumpBase implements IDump {
     this._files = files;
   }
 
-  get files(): any[] {
+  get files(): readonly any[] {
     return Object.values(this._files).flat();
   }
 
@@ -31,6 +31,6 @@ export default abstract class DumpBase implements IDump {
 }
 
 interface IDump {
-  files: Array<Object>;
+  files: readonly Object[];
   type: String,
 }
\ No newline at end of file
diff --git a/tools/winscope/src/main.js b/tools/winscope/src/main.js
index 88aa5f5a2..587f42519 100644
--- a/tools/winscope/src/main.js
+++ b/tools/winscope/src/main.js
@@ -165,7 +165,9 @@ const store = new Vuex.Store({
         }
 
         if (Object.keys(traceFiles).length > 0 && typeInfo.constructor) {
-          traces[traceType] = new typeInfo.constructor(traceFiles);
+          const newObj = new typeInfo.constructor(traceFiles);
+          newObj.data = Object.freeze(newObj.data);
+          traces[traceType] = newObj;
         }
       }
 
@@ -198,7 +200,9 @@ const store = new Vuex.Store({
         }
 
         if (Object.keys(dumpFiles).length > 0 && typeInfo.constructor) {
-          dumps[dumpType] = new typeInfo.constructor(dumpFiles);
+          const newObj = new typeInfo.constructor(dumpFiles);
+          newObj.data = Object.freeze(newObj.data);
+          dumps[dumpType] = newObj;
         }
 
       }
diff --git a/tools/winscope/src/traces/SurfaceFlinger.ts b/tools/winscope/src/traces/SurfaceFlinger.ts
index 049dc684a..b8ec6df93 100644
--- a/tools/winscope/src/traces/SurfaceFlinger.ts
+++ b/tools/winscope/src/traces/SurfaceFlinger.ts
@@ -19,15 +19,15 @@ import TraceBase from './TraceBase';
 import { LayersTrace } from '@/flickerlib';
 
 export default class SurfaceFlinger extends TraceBase {
-  sfTraceFile: Object;
-  tagGenerationTrace: Object;
+  readonly sfTraceFile: Object;
+  readonly tagGenerationTrace: Object;
 
   constructor(files) {
-    const sfTraceFile = files[FILE_TYPES.SURFACE_FLINGER_TRACE];
+    const sfTraceFile = Object.freeze(files[FILE_TYPES.SURFACE_FLINGER_TRACE]);
     const tagGenerationTrace = files[FILE_TYPES.SURFACE_FLINGER_TRACE].tagGenerationTrace;
     super(sfTraceFile.data, sfTraceFile.timeline, files);
 
-    this.tagGenerationTrace = tagGenerationTrace;
+    this.tagGenerationTrace = Object.freeze(tagGenerationTrace);
     this.sfTraceFile = sfTraceFile;
   }
 
diff --git a/tools/winscope/src/traces/TraceBase.ts b/tools/winscope/src/traces/TraceBase.ts
index 652dc7ee0..ab9666c6d 100644
--- a/tools/winscope/src/traces/TraceBase.ts
+++ b/tools/winscope/src/traces/TraceBase.ts
@@ -23,9 +23,9 @@ import JSZip from 'jszip';
 
 export default abstract class Trace implements ITrace {
   selectedIndex: Number;
-  data: Object;
-  timeline: Array<Number>;
-  _files: File[];
+  readonly data: Object;
+  readonly timeline: Array<Number>;
+  readonly _files: File[];
 
   constructor(data: any, timeline: Number[], files: any[]) {
     this.selectedIndex = 0;
@@ -34,7 +34,7 @@ export default abstract class Trace implements ITrace {
     this._files = files;
   }
 
-  get files(): File[] {
+  get files(): readonly File[] {
     return Object.values(this._files).flat();
   }
 
@@ -64,6 +64,6 @@ export default abstract class Trace implements ITrace {
 }
 
 interface ITrace {
-  files: Array<Object>;
+  files: readonly Object[];
   type: String,
-}
\ No newline at end of file
+}