⚡ Bolt: [성능 개선] 검색어 입력 시 발생하는 다량의 GC 부하 및 불필요한 배열 메모리 할당 최적화

.jules/bolt.md

@@ -60,3 +60,6 @@ Optimized metric route processing to O(N) by creating a mapping of routes direct
 ## 2026-06-25 - Avoid Map allocations in frontend ERD loops and mutate asyncpg records in-place
 **Learning:** The frontend `snapshotToGraph` iterates over thousands of columns to generate the graph, so repeated lookups and redundant collection assignments increase GC pressure. Backend snapshot column dictionaries are freshly instantiated for the payload, so `add_column_examples` can safely fill missing fields in place.
 **Action:** Reuse existing collections while aggregating relational data, create `Map`/`Set` entries only on first use, and check for missing example fields before calling expensive inference helpers.
+## 2024-07-25 - Avoid flatMap and join for High-Frequency String Building
+**Learning:** During real-time operations like typing in a search bar, iterating over dynamically sized React state arrays with `.flatMap()` and `.join(" ")` creates excessive short-lived intermediate arrays and strings, causing severe garbage collection pressure and main thread blocking.
+**Action:** Replace functional `.flatMap().join()` chains with explicit loops and standard iterative string concatenation (`+=`) for performance-critical string searching over collections of nodes.

frontend/src/App.tsx

@@ -182,17 +182,17 @@ export default function App() {
     if (!normalizedNodeSearch) return new Set<string>();
     const matches = new Set<string>();
     for (const node of nodes) {
-      const haystack = [
-        node.data.title,
-        node.data.comment ?? "",
-        ...node.data.columns.flatMap((column) => [
-          column.column_name,
-          column.data_type,
-          column.column_comment ?? "",
-        ]),
-      ]
-        .join(" ")
-        .toLocaleLowerCase();
+      let haystack = node.data.title;
+      if (node.data.comment) {
+        haystack += " " + node.data.comment;
+      }
+      for (const column of node.data.columns) {
+        haystack += " " + column.column_name + " " + column.data_type;
+        if (column.column_comment) {
+          haystack += " " + column.column_comment;
+        }
+      }
+      haystack = haystack.toLocaleLowerCase();
       if (haystack.includes(normalizedNodeSearch)) {
         matches.add(node.id);
       }