diigo-cache: pace diigo calls only; cache hits don't wait

page() ran the 500 ms pacing gate before the cache check, so every hit
waited too: a fill rerun skipping 166 cached pages took ~80 s and
looked like a start from scratch. The gate now sits after the hit
check (re-checking storage once through it, in case a request ahead
had just etched the page).

Regression test: the fixed-clock test cache records its sleeps; a miss
sleeps once, three hits add none (failed before: 4 sleeps).

Generated-by: Claude Opus 5.5

diigo-cache/src/cache.ts

@@ -285,8 +285,15 @@ abstract class PagedCache extends DurableObject<CacheEnv> {
 		if (!init) throw new Error("not wired: this cache id was never set up");
 		this.ctx.storage.sql.exec(SCHEMA_V1);
 
-		// one diigo call path at a time, min spacing MS_PER_CALL (webapp's
-		// Gate pattern; per activation)
+		const hit = await this.#pageFromStorage(pageNum, count);
+		if (hit) {
+			console.log({ event: "cache", kind: this.kind, page: pageNum, outcome: "hit", items: hit.items.length });
+			return hit;
+		}
+
+		// a miss calls diigo: one call path at a time, min spacing
+		// MS_PER_CALL (webapp's Gate pattern; per activation). Hits above
+		// never wait.
 		let before;
 		do {
 			before = this.#step;
@@ -294,11 +301,11 @@ abstract class PagedCache extends DurableObject<CacheEnv> {
 		} while (before !== this.#step);
 		this.#step += 1;
 		this.#pause = this.#clock.sleep(MS_PER_CALL);
-
-		const hit = await this.#pageFromStorage(pageNum, count);
-		if (hit) {
-			console.log({ event: "cache", kind: this.kind, page: pageNum, outcome: "hit", items: hit.items.length });
-			return hit;
+		// a request ahead of us at the gate may have etched this page
+		const late = await this.#pageFromStorage(pageNum, count);
+		if (late) {
+			console.log({ event: "cache", kind: this.kind, page: pageNum, outcome: "hit", items: late.items.length });
+			return late;
 		}
 
 		// RPC stubs (the app and each pipelined step) are disposed once the

diigo-cache/tests/caches.test.ts

@@ -12,6 +12,7 @@ const WEBAPP_ID = "fake-webapp-id";
 type TestEnv = {
 	CACHE_DO: DurableObjectNamespace<import("../src/index.js").DiigoCache>;
 	PUBLIC_DO: DurableObjectNamespace<import("../src/index.js").PublicCache>;
+	CLOCKED_DO: DurableObjectNamespace<import("./test-worker.js").FixedClockCache>;
 	WEBAPP: { calls(): Promise<number> };
 };
 const testEnv = env as unknown as TestEnv;
@@ -109,6 +110,18 @@ describe("page size", () => {
 	});
 });
 
+describe("pacing", () => {
+	it("paces diigo calls only: a cache hit doesn't wait", async () => {
+		const stub = testEnv.CLOCKED_DO.get(testEnv.CLOCKED_DO.newUniqueId());
+		await stub.setup({ webappId: WEBAPP_ID });
+		await stub.page(1, PAGE_SIZE);
+		const afterMiss = (await stub.sleeps()).length;
+		expect(afterMiss).toBeGreaterThan(0);
+		for (let i = 0; i < 3; i += 1) expect((await stub.page(1, PAGE_SIZE)).cached).toBe(true);
+		expect(await stub.sleeps()).toHaveLength(afterMiss);
+	});
+});
+
 describe("eviction", () => {
 	it("a cache miss leaves no undisposed RPC stubs to block eviction", async () => {
 		const stub = testEnv.CACHE_DO.get(testEnv.CACHE_DO.newUniqueId());

diigo-cache/tests/test-worker.ts

@@ -12,8 +12,23 @@ export { default } from "../src/index.js";
 /** 2026-10-07T12:00:00Z */
 export const FIXED_NOW = Date.UTC(2026, 9, 7, 12, 0, 0);
 
+/** a fixed clock that records each sleep it is asked for */
 export class FixedClockCache extends DiigoCacheLogic {
+	#sleeps: number[] = [];
+
 	constructor(ctx: DurableObjectState, env: CacheEnv) {
-		super(ctx, env, { now: () => FIXED_NOW, sleep: async () => {} });
+		const sleeps: number[] = [];
+		super(ctx, env, {
+			now: () => FIXED_NOW,
+			sleep: async (ms) => {
+				sleeps.push(ms);
+			},
+		});
+		this.#sleeps = sleeps;
+	}
+
+	/** the sleeps so far (test hook) */
+	async sleeps(): Promise<number[]> {
+		return [...this.#sleeps];
 	}
 }