diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4cf6edf6c7..45078094ae 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@
 - 🙌 Stop computing outdated diagnostics with CancellationToken. Thanks to contribution from [@yoyo930021](https://github.com/yoyo930021). #1263 and #2332.
 - 🙌 Fix error when optional camel-cased props are missing. Thanks to contribution from [@yoyo930021](https://github.com/yoyo930021). #2314 and #2342.
 - 🙌 Fix Vetur formatting not working. Thanks to contribution from [@yoyo930021](https://github.com/yoyo930021). #2388 and #2389.
+- 🙌 Improve ts perf when `vetur.experimental.templateInterpolationService: true`. Thanks to contribution from [@yoyo930021](https://github.com/yoyo930021). #2192 and #2374.
 
 ### 0.28.0 | 2020-09-23 | [VSIX](https://marketplace.visualstudio.com/_apis/public/gallery/publishers/octref/vsextensions/vetur/0.28.0/vspackage)
 
diff --git a/server/src/services/typescriptService/preprocess.ts b/server/src/services/typescriptService/preprocess.ts
index 04ad59b6e4..1dfe374f2d 100644
--- a/server/src/services/typescriptService/preprocess.ts
+++ b/server/src/services/typescriptService/preprocess.ts
@@ -122,6 +122,14 @@ export function createUpdater(tsModule: T_TypeScript, allChildComponentsInfo: Ma
       true /* setParentNodes: Need this to walk the AST */,
       tsModule.ScriptKind.JS
     );
+    // Assign version to the new template sourceFile to avoid re-processing
+    // *internal* property
+    (newSourceFile as any).version = (sourceFile as any).version;
+    (newSourceFile as any).scriptSnapshot = {
+      getText: (start: number, end: number) => newText.substring(start, end),
+      getLength: () => newText.length,
+      getChangeRange: () => void 0
+    };
 
     const templateFsPath = URI.file(vueTemplateFileName).fsPath;
     const sourceMapNodes = generateSourceMap(tsModule, sourceFile, newSourceFile);
@@ -179,7 +187,7 @@ function modifyVueScript(tsModule: T_TypeScript, sourceFile: ts.SourceFile): voi
     st =>
       st.kind === tsModule.SyntaxKind.ExportAssignment &&
       (st as ts.ExportAssignment).expression.kind === tsModule.SyntaxKind.ObjectLiteralExpression
-  );
+  ) as ts.ExportAssignment;
   if (exportDefaultObject) {
     // 1. add `import Vue from 'vue'
     // (the span of the inserted statement must be (0,0) to avoid overlapping existing statements)
@@ -204,7 +212,7 @@ function modifyVueScript(tsModule: T_TypeScript, sourceFile: ts.SourceFile): voi
       end: objectLiteral.pos + 1
     });
     (exportDefaultObject as any).expression = setObjPos(tsModule.createCall(vue, undefined, [objectLiteral]));
-    setObjPos(((exportDefaultObject as ts.ExportAssignment).expression as ts.CallExpression).arguments!);
+    setObjPos((exportDefaultObject.expression as ts.CallExpression).arguments!);
   }
 }