@@ -1,4 +1,5 @@
 // Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+// test-budget: 40 — spawns the real producer once per single-cause fixture: three in-process kernel boots on a real SQL driver, the first seeding 2,600 comments on 260 docs through the real writers to sit past the 2,000-row window the comment gate replaced; slowest CI reading 28.07 s (run 40204927516, refresh PR #25960's window (hourly runs 40200279306 to 40272142430)) x 1.25, rounded up; read before this file seeded its comments ten to a doc and paid its first boot at module scope
 
 /**
  * [ADR-0139 E7] The comment-thread read gate on the LEAF path, over
@@ -55,9 +56,19 @@ const DELEGATED_A = { ...MEMBER_A, onBehalfOf: { userId: 'u_delegator' } };
 /** The delegator's own leg on `e7_doc` admits every record but these (by name). */
 const WITHHELD_FROM_DELEGATOR = ['a0', 'a1', 'a2'];
 
-/** Past the 2,000-row candidate window the leaf replaces. */
-const DOCS_OF_A = 2_300;
-const DOCS_OF_B = 300;
+/**
+ * Past the 2,000-row candidate window the leaf replaces: 2,300 comments member
+ * A may read, 300 member B may. The window was over COMMENT rows (the thread
+ * probe's candidate pre-scan reads `sys_comment`, `READ_SCAN_LIMIT` in
+ * `comment-access-hooks.ts`), never over parent records, so the comments sit
+ * ten to a doc. [#23181] One comment per doc wrote 2,600 docs, and each doc
+ * write pays the CRUD mirror's ledger row and activity row, which nothing in
+ * this file reads: about 6 s of the file's clock, against well under 1 s for
+ * the comments themselves.
+ */
+const COMMENTS_PER_DOC = 10;
+const DOCS_OF_A = 230;
+const DOCS_OF_B = 30;
 const BATCH = 200;
 
 const READ_OPS = new Set(['find', 'findOne', 'count', 'aggregate']);
@@ -145,6 +156,12 @@ const commentOn = (object: string, id: string, body: string): Row => ({
   author_id: 'u_fixture',
 });
 
+// [#23181] Pay the first kernel boot at module scope, never in a hook: vitest
+// clocks a hook as it clocks a test, and the first boot is the slow one. The
+// throwaway kernel registers no fixture object, writes nothing and is shut down
+// before any hook runs.
+await (await bootKernel(new SqliteWasmDriver({ filename: ':memory:' }))).kernel.shutdown();
+
 describe('[ADR-0139 E7] the comment-thread read gate over the stamped parent pair', () => {
   let kernel: ObjectKernel;
   let engine: ObjectQL;
@@ -209,7 +226,8 @@ describe('[ADR-0139 E7] the comment-thread read gate over the stamped parent pai
     for (let i = 0; i < DOCS_OF_A; i++) docs.push({ name: `a${i}`, owner: MEMBER_A.userId });
     for (let i = 0; i < DOCS_OF_B; i++) docs.push({ name: `b${i}`, owner: MEMBER_B.userId });
     const docIds = await insertInBatches(engine, DOC, docs);
-    await insertInBatches(engine, COMMENT, docIds.map((id, i) => commentOn(DOC, id, `c${i}`)));
+    await insertInBatches(engine, COMMENT, docIds.flatMap((id, i) =>
+      Array.from({ length: COMMENTS_PER_DOC }, (_, k) => commentOn(DOC, id, `c${i * COMMENTS_PER_DOC + k}`))));
 
     ids.gone = String((await engine.insert(DOC, { name: 'gone', owner: MEMBER_A.userId }, { context: SYS })).id);
     ids.vault = String((await engine.insert(VAULT, { name: 'vault' }, { context: SYS })).id);
 
@@ -1,4 +1,5 @@
 // Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+// test-budget: 50 — spawns the real producer once per single-cause fixture: two in-process kernel boots on a real SQL driver, the first seeding 2,600 records through the real CRUD mirror (each pays its activity row and its ledger row) to sit past the 2,000-row window the leaf gate replaced; slowest CI reading 35.78 s (run 40204927516, refresh PR #25960's window (hourly runs 40200279306 to 40272142430)) x 1.25, rounded up; read before this file reused its at-rest reads and paid its first boot at module scope
 
 /**
  * [ADR-0139 E5] The parent-record read gates on the LEAF path, through a real
@@ -180,6 +181,12 @@ async function insertInBatches(engine: ObjectQL, object: string, rows: Row[]): P
   }
 }
 
+// [#23181] Pay the first kernel boot at module scope, never in a hook: vitest
+// clocks a hook as it clocks a test, and the first boot is the slow one. The
+// throwaway kernel registers no fixture object, writes nothing and is shut down
+// before any hook runs.
+await (await bootKernel(new SqliteWasmDriver({ filename: ':memory:' }))).kernel.shutdown();
+
 describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
   let kernel: ObjectKernel;
   let engine: ObjectQL;
@@ -201,12 +208,30 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
   const ledgerOrganizationBound: boolean[] = [];
   const ids: Record<string, string> = {};
 
+  /**
+   * [#23181] Every row of an object at rest, as the system reads it — read once
+   * and reused. No case in this describe writes after `beforeAll`, so each such
+   * read answered the same rows: the cases made nearly seventy of them, most
+   * over tables of thousands of rows. Each reuse counts the object first and
+   * re-reads on a moved count, so a case that adds or removes rows is never
+   * judged against an older ground truth.
+   */
+  const atRestCache = new Map<string, { count: number; rows: Row[] }>();
+  const atRestOf = async (object: string): Promise<Row[]> => {
+    const count = await engine.count(object, {}, { context: SYS });
+    const hit = atRestCache.get(object);
+    if (hit && hit.count === count) return hit.rows;
+    const rows: Row[] = await engine.find(object, { limit: 100_000, context: SYS });
+    atRestCache.set(object, { count, rows });
+    return rows;
+  };
+
   /** Every row at rest, and the ground truth of who may read which, judged by the stand-in's own rules. */
   const truth = async (object: string, reader: any): Promise<string[]> => {
-    const atRest: Row[] = await engine.find(object, { limit: 100_000, context: SYS });
+    const atRest = await atRestOf(object);
     const live = new Map<string, Map<string, Row>>();
     for (const parent of [DOC, VAULT, GATED, FAR]) {
-      const records: Row[] = await engine.find(parent, { limit: 100_000, context: SYS });
+      const records = await atRestOf(parent);
       live.set(parent, new Map(records.map((r) => [String(r.id), r])));
     }
     const holder = Array.isArray(reader?.systemPermissions) && reader.systemPermissions.includes(LEDGER_AUDIT_CAPABILITY);
@@ -298,12 +323,12 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
   }, 30_000);
 
   it('control: the fixture is past the window, and every row came from its producer', async () => {
-    const activity: Row[] = await engine.find(ACTIVITY, { limit: 100_000, context: SYS });
+    const activity = await atRestOf(ACTIVITY);
     expect(activity.length).toBeGreaterThan(PARENT_GATE_SCAN_LIMIT);
     expect(activity.filter((r) => r.object_name === DOC && r.type === 'created').length).toBe(DOCS_OF_A + DOCS_OF_B + 1);
     expect(activity.some((r) => r.object_name === DOC && r.record_id === ids.gone && r.type === 'deleted')).toBe(true);
     expect((await truth(ACTIVITY, MEMBER_A)).length).toBeGreaterThan(PARENT_GATE_SCAN_LIMIT);
-    const ledger: Row[] = await engine.find(LEDGER, { limit: 100_000, context: SYS });
+    const ledger = await atRestOf(LEDGER);
     expect(ledger.filter((r) => r.action === 'config_change').length).toBe(ROWS_ABOUT_NO_RECORD);
   });
 
@@ -328,7 +353,7 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
   });
 
   it('no row is served whose parent the reader may not read, or that no longer exists', async () => {
-    const all: Row[] = await engine.find(ACTIVITY, { limit: 100_000, context: SYS });
+    const all = await atRestOf(ACTIVITY);
     const byId = new Map(all.map((r) => [String(r.id), r]));
     for (const id of await served(ACTIVITY, MEMBER_A)) {
       const row = byId.get(id)!;
@@ -379,7 +404,7 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
     const named = { object_name: { $in: NAMED } };
     // The same rows, in a spelling the gate does not read as naming its parents: it keeps every branch.
     const spelledOut = { $or: NAMED.map((object_name) => ({ object_name })) };
-    const atRest: Row[] = await engine.find(ACTIVITY, { limit: 100_000, context: SYS });
+    const atRest = await atRestOf(ACTIVITY);
     const parentOf = new Map(atRest.map((r) => [String(r.id), r.object_name]));
     const gateConjunct = (where: any) => where.$and[1];
     seenWhere[ACTIVITY].length = 0;
@@ -431,7 +456,7 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
     // per parent object through the engine middleware chain, with the
     // delegated context. Asked here for every parent pair at rest, so no
     // window cuts it; the leaf must serve exactly the rows it admits.
-    const atRest: Row[] = await engine.find(ACTIVITY, { limit: 100_000, context: SYS });
+    const atRest = await atRestOf(ACTIVITY);
     const pairs = new Map<string, Set<string>>();
     for (const row of atRest) {
       const parent = parseParentRecord(row, ACTIVITY);
@@ -488,7 +513,7 @@ describe('[ADR-0139 E5] the parent-record read gates on the leaf path', () => {
       return Math.round((performance.now() - t0) * 10) / 10;
     };
     const reading = {
-      rowsAtRest: (await engine.find(ACTIVITY, { limit: 100_000, context: SYS })).length,
+      rowsAtRest: (await atRestOf(ACTIVITY)).length,
       leafMs: {
         memberFind: await time(() => served(ACTIVITY, MEMBER_A)),
         memberCount: await time(() => engine.count(ACTIVITY, {}, { context: MEMBER_A })),