⚡ Bolt: sanitizeHandleId의 Array.from 최적화를 통한 GC 오버헤드 감소

.jules/bolt.md

@@ -77,3 +77,7 @@ Optimized metric route processing to O(N) by creating a mapping of routes direct
 ## 2024-07-13 - [Optimize Export Dictionary FK lookups]
 **Learning:** Found O(N * C * E) performance bottleneck in ERD export dictionaries due to repeated array searching with `edges.some()` inside a nested loop over nodes and columns.
 **Action:** Replace repeated linear array scans for edges by precomputing O(1) Set lookups of foreign key column handles per node before looping.
+
+## 2024-08-17 - Optimize Array.from for GC Overhead in sanitizeHandleId
+**Learning:** Using `Array.from(string)` to iterate over strings creates intermediate array allocations, increasing garbage collection overhead. In hot paths like frontend ERD graph processing (`sanitizeHandleId` in `handleUtils.ts`), removing these allocations provides a measurable performance improvement.
+**Action:** Replace `Array.from()` with an iterative `for...of` loop in high-frequency string processing functions to avoid intermediate array instantiation and reduce GC pressure.

frontend/src/erd/handleUtils.ts

@@ -1,16 +1,23 @@
 export function sanitizeHandleId(columnName: string): string {
-  const encoded = Array.from(columnName, (char) => {
-    // Array.from only yields non-empty Unicode scalars, so codePointAt(0) is defined.
-    return char.codePointAt(0)!.toString(16).padStart(4, '0')
-  }).join('-')
+  if (!columnName) return 'c-empty';
 
-  return `c-${encoded || 'empty'}`
+  let encoded = '';
+  let isFirst = true;
+  for (const char of columnName) {
+    if (!isFirst) {
+      encoded += '-';
+    }
+    encoded += char.codePointAt(0)!.toString(16).padStart(4, '0');
+    isFirst = false;
+  }
+
+  return `c-${encoded}`;
 }
 
 export function sourceColumnHandleId(columnName: string): string {
-  return `src-${sanitizeHandleId(columnName)}`
+  return `src-${sanitizeHandleId(columnName)}`;
 }
 
 export function targetColumnHandleId(columnName: string): string {
-  return `tgt-${sanitizeHandleId(columnName)}`
+  return `tgt-${sanitizeHandleId(columnName)}`;
 }