⚡ Bolt: [성능 개선] 핫 패스에서 Object.keys를 for...in으로 교체 및 안전성 보강

packages/web/src/lib/server/daily-rollup.ts

@@ -438,16 +438,16 @@ export async function getDailyRollupsForProjects(
         const userSet = userSetsByDate.get(r.date)!
         for (const u of r.activeUserIds) userSet.add(u)
 
-        // [Bolt: Performance Optimization] Use Object.keys() instead of Object.entries() in hot paths.
-        // Impact: Avoids array allocation for each key-value pair, significantly reducing GC overhead when aggregating large daily rollups.
-        for (const k of Object.keys(r.skillCounts)) {
-          prev.skillCounts[k] = (prev.skillCounts[k] ?? 0) + r.skillCounts[k]!
+        // [Bolt: Performance Optimization] Use for...in instead of Object.keys() in hot paths.
+        // Impact: Completely avoids array allocation for each key set, significantly reducing GC overhead when aggregating large daily rollups.
+        for (const k in r.skillCounts) {
+          if (Object.hasOwn(r.skillCounts, k)) prev.skillCounts[k] = (prev.skillCounts[k] ?? 0) + r.skillCounts[k]!
         }
-        for (const k of Object.keys(r.agentCounts)) {
-          prev.agentCounts[k] = (prev.agentCounts[k] ?? 0) + r.agentCounts[k]!
+        for (const k in r.agentCounts) {
+          if (Object.hasOwn(r.agentCounts, k)) prev.agentCounts[k] = (prev.agentCounts[k] ?? 0) + r.agentCounts[k]!
         }
-        for (const k of Object.keys(r.modelTokens)) {
-          prev.modelTokens[k] = (prev.modelTokens[k] ?? 0) + r.modelTokens[k]!
+        for (const k in r.modelTokens) {
+          if (Object.hasOwn(r.modelTokens, k)) prev.modelTokens[k] = (prev.modelTokens[k] ?? 0) + r.modelTokens[k]!
         }
 
         // userStats: userId 기준 sum (지연된 Map 변환)
@@ -622,10 +622,10 @@ export function aggregateSummary(
     totals.cacheCreationTokens += r.cacheCreationTokens
     totals.estimatedCostUsd += r.estimatedCostUsd
     for (const u of r.activeUserIds) activeUsers.add(u)
-    // [Bolt: Performance Optimization] Object.keys() iterations avoid internal array tuples, reducing heap thrashing
-    for (const k of Object.keys(r.skillCounts)) skillCounts[k] = (skillCounts[k] ?? 0) + r.skillCounts[k]!
-    for (const k of Object.keys(r.agentCounts)) agentCounts[k] = (agentCounts[k] ?? 0) + r.agentCounts[k]!
-    for (const k of Object.keys(r.modelTokens)) modelTokens[k] = (modelTokens[k] ?? 0) + r.modelTokens[k]!
+    // [Bolt: Performance Optimization] for...in iterations avoid internal array tuples and keys array allocation, reducing heap thrashing
+    for (const k in r.skillCounts) if (Object.hasOwn(r.skillCounts, k)) skillCounts[k] = (skillCounts[k] ?? 0) + r.skillCounts[k]!
+    for (const k in r.agentCounts) if (Object.hasOwn(r.agentCounts, k)) agentCounts[k] = (agentCounts[k] ?? 0) + r.agentCounts[k]!
+    for (const k in r.modelTokens) if (Object.hasOwn(r.modelTokens, k)) modelTokens[k] = (modelTokens[k] ?? 0) + r.modelTokens[k]!
   }
 
   // Deterministic tie-break: callCount DESC, skillName ASC (codepoint binary —

packages/web/src/lib/server/weekly-report.ts

@@ -394,19 +394,21 @@ export async function getWeeklyReport(
   // Insights — delegation
   // ⚡ Bolt Optimization:
   // 병목 지점: 기존 코드는 `thisWeekRollups`를 3번 순회하고, 매 순회마다 Object.values()로 중간 배열을 생성하여 메모리 할당 비용이 발생했습니다.
-  // 최적화 방법: 단일 for...of 루프와 Object.keys() 순회를 결합하여 N+1 순회를 1회 순회로 통합하고 중간 배열 할당을 제거했습니다.
-  // 기대 효과: `thisWeekRollups`의 크기가 클 경우, 불필요한 배열 생성 오버헤드와 O(N) 순회를 1/3로 줄여 리포트 생성 성능이 향상됩니다.
+  // 최적화 방법: 단일 for...of 루프와 for...in 순회를 결합하여 배열 할당을 완전히 제거하고 N+1 순회를 1회로 통합했습니다.
+  // 기대 효과: `thisWeekRollups`의 크기가 클 경우, 불필요한 배열 생성 오버헤드 및 O(N) 순회를 1/3로 줄이고 GC 오버헤드를 대폭 감소시켜 리포트 생성 성능이 향상됩니다.
   let totalAgentCalls = 0
   let totalSkillCalls = 0
   const distinctSkillsThisWeek = new Set<string>()
 
   for (const r of thisWeekRollups) {
-    for (const k of Object.keys(r.agentCounts)) {
-      totalAgentCalls += r.agentCounts[k]
+    for (const k in r.agentCounts) {
+      if (Object.hasOwn(r.agentCounts, k)) totalAgentCalls += r.agentCounts[k]
     }
-    for (const k of Object.keys(r.skillCounts)) {
-      totalSkillCalls += r.skillCounts[k]
-      distinctSkillsThisWeek.add(k)
+    for (const k in r.skillCounts) {
+      if (Object.hasOwn(r.skillCounts, k)) {
+        totalSkillCalls += r.skillCounts[k]
+        distinctSkillsThisWeek.add(k)
+      }
     }
   }