From 60e6ba55d77ba796ab4321fe01bdfa11e83c47b6 Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 2 Jul 2026 21:15:47 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Batched=20GC=20operations?=
 =?UTF-8?q?=20for=20ArtifactStore?=
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Content-Type: text/plain; charset=UTF-8
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Optimized sequential `fs.stat` and `fs.rm` calls in `ArtifactStore.gc` into batched concurrent operations using `Promise.all` (chunk size 10), preserving array order for correctness.
---
 .jules/bolt.md                             |  3 ++
 src/core/sub-agent/artifacts/store.ts      | 42 +++++++++++++++++-----
 tests/integration/prompt_templates.test.ts |  4 ++-
 3 files changed, 39 insertions(+), 10 deletions(-)
 create mode 100644 .jules/bolt.md

diff --git a/.jules/bolt.md b/.jules/bolt.md
new file mode 100644
index 00000000..283330f8
--- /dev/null
+++ b/.jules/bolt.md
@@ -0,0 +1,3 @@
+## 2025-02-12 - Batched I/O for GC performance
+**Learning:** Concurrent array mutation inside Promise.all chunking produces non-deterministic order, causing subtle bugs in artifact GC which relies on predictable sorting.
+**Action:** Always map Promise.all results and iterate sequentially to apply mutations or maintain order.
diff --git a/src/core/sub-agent/artifacts/store.ts b/src/core/sub-agent/artifacts/store.ts
index 8a7aff5c..d041ced2 100644
--- a/src/core/sub-agent/artifacts/store.ts
+++ b/src/core/sub-agent/artifacts/store.ts
@@ -93,13 +93,35 @@ export class ArtifactStore {
     const entries = await fs.readdir(root, { withFileTypes: true }).catch(() => []);
 
     const files: Array<{ name: string; path: string; mtimeMs: number; size: number }> = [];
-    for (const entry of entries) {
-      if (!entry.isFile()) continue;
-      const filePath = path.join(root, entry.name);
-      if (!isWithinDir(root, filePath)) continue;
-      const stat = await fs.stat(filePath).catch(() => null);
-      if (!stat) continue;
-      files.push({ name: entry.name, path: filePath, mtimeMs: stat.mtimeMs, size: stat.size });
+    // Batch fs.stat calls for performance
+    const validEntries = entries.filter((e) => {
+      if (!e.isFile()) return false;
+      const filePath = path.join(root, e.name);
+      return isWithinDir(root, filePath);
+    });
+
+    for (let i = 0; i < validEntries.length; i += 10) {
+      const chunk = validEntries.slice(i, i + 10);
+      const results = await Promise.all(
+        chunk.map(async (entry) => {
+          const filePath = path.join(root, entry.name);
+          const stat = await fs.stat(filePath).catch(() => null);
+          return stat
+            ? {
+                name: entry.name,
+                path: filePath,
+                mtimeMs: stat.mtimeMs,
+                size: stat.size,
+              }
+            : null;
+        }),
+      );
+
+      for (const result of results) {
+        if (result) {
+          files.push(result);
+        }
+      }
     }
 
     const maxAgeMs = options?.maxAgeMs ?? LIMITS.artifactTtlMs;
@@ -118,8 +140,10 @@ export class ArtifactStore {
       removedBytes += file.size;
     };
 
-    for (const file of expired) {
-      await removeFile(file);
+    // Batch expired file deletion for performance
+    for (let i = 0; i < expired.length; i += 10) {
+      const chunk = expired.slice(i, i + 10);
+      await Promise.all(chunk.map(removeFile));
     }
 
     // Recompute remaining after TTL removal (newest first).
diff --git a/tests/integration/prompt_templates.test.ts b/tests/integration/prompt_templates.test.ts
index 21905259..f1360d78 100644
--- a/tests/integration/prompt_templates.test.ts
+++ b/tests/integration/prompt_templates.test.ts
@@ -36,7 +36,9 @@ describe('Prompt templates', () => {
 
     expect(planSystem).toContain('You are SalmonLoop.');
     expect(patchSystem).toContain('You are PATCH, a phase-native diff compiler.');
-    expect(autopilotSystem).toContain('You are a senior software engineer running in "autopilot" mode.');
+    expect(autopilotSystem).toContain(
+      'You are a senior software engineer running in "autopilot" mode.',
+    );
     expect(answerSystem).toContain('You are a coding assistant in "answer" mode.');
     expect(researchSystem).toContain('You are a research assistant.');
   });