perf(cache): reduce response store Durable Object load

examples/workers-cache/README.md

@@ -1,6 +1,6 @@
 # Workers Response Store adapter POC
 
-This example uses one `responseStoreAdapter()` from `@vinext/cloudflare` in place of both `cdnAdapter()` and `kvDataAdapter()`. The application Worker keeps Workers Cache disabled. Its `RESPONSE_STORE` service binding calls a separately deployed cache Worker that owns Workers Cache, R2 response bodies, SQLite Durable Object metadata, tag indexes, and SWR regeneration.
+This example uses one `responseStoreAdapter()` from `@vinext/cloudflare` in place of both `cdnAdapter()` and `kvDataAdapter()`. The application Worker keeps Workers Cache disabled. Its `RESPONSE_STORE` service binding calls a separately deployed cache Worker that owns Workers Cache, R2 response bodies, SQLite Durable Object metadata and tag invalidation timestamps, and SWR regeneration.
 
 The cache Worker is shared infrastructure, not a second deployment of the application. Each application version has one ordinary build and deploy. Cached entries retain a loopback to that application version's vinext response-stage entrypoint. Route and fetch-cache entries can replay that stage, while a transformed public `"use cache"` entry records its encrypted arguments and server-reference identity so regeneration invokes only that function. If its arguments cannot be safely recorded, the adapter falls back to replaying the cacheable route.
 

packages/cloudflare/src/cache/response-store-adapter.worker.ts

@@ -400,6 +400,7 @@ export default {
                 return;
               }
               await responseStore.put(key, admitted, {
+                coalesce: true,
                 revalidator: { id: ROUTE_REVALIDATOR_ID, args: [invocation] },
               });
             })
@@ -426,6 +427,7 @@ export default {
       const [foreground, cacheBody] = rendered.body ? rendered.body.tee() : [null, null];
       const cacheResponse = new Response(cacheBody, rendered);
       await responseStore.put(key, cacheResponse, {
+        coalesce: true,
         revalidator: { id: ROUTE_REVALIDATOR_ID, args: [invocation] },
       });
 
@@ -446,7 +448,10 @@ export default {
             headers: rscHeaders,
             status: 200,
           }),
-          { revalidator: { id: ROUTE_REVALIDATOR_ID, args: [rscInvocation] } },
+          {
+            coalesce: true,
+            revalidator: { id: ROUTE_REVALIDATOR_ID, args: [rscInvocation] },
+          },
         );
       }
       return publicResponse(new Response(foreground, rendered), "MISS");

packages/cloudflare/src/cache/response-store-data.runtime.ts

@@ -442,6 +442,7 @@ export class WorkersResponseStoreCacheHandler implements CacheHandler {
 
     await this.store.put(await cacheRequest(key), response, {
       ...(revalidator ? { revalidator } : {}),
+      coalesce: true,
       purgeExisting: true,
     });
   }

packages/cloudflare/tests/response-store-adapter.e2e.test.ts

@@ -285,7 +285,7 @@ describe("Cloudflare Workers Response Store adapter", () => {
     assert.doesNotMatch(serialized, /first-secret|second-secret/);
   });
 
-  test("keeps concurrent cold renders successful when a cache write loses CAS", async () => {
+  test("keeps concurrent cold renders successful", async () => {
     const responses = await Promise.all(
       Array.from({ length: 8 }, () => request("/cached/concurrent")),
     );

packages/cloudflare/tests/response-store-data.test.ts

@@ -70,6 +70,7 @@ test("only attaches loopback regeneration to replayable requests", async () => {
     handler.set("get", null, { cacheControl: { revalidate: 1, expire: 2 } }),
   );
   expect(store.options).toMatchObject({
+    coalesce: true,
     purgeExisting: true,
     revalidator: { id: "vinext:data", args: ["get", "safe-get"] },
   });
@@ -78,7 +79,7 @@ test("only attaches loopback regeneration to replayable requests", async () => {
   await runWithResponseStoreInvocation("unsafe-post", false, () =>
     handler.set("post", null, { cacheControl: { revalidate: 1, expire: 2 } }),
   );
-  expect(store.options).toEqual({ purgeExisting: true });
+  expect(store.options).toEqual({ coalesce: true, purgeExisting: true });
   expect(store.response?.headers.get("X-Vinext-Response-Store-Replayable")).toBeNull();
   expect(store.response?.headers.get("Cache-Control")).toBe("public, max-age=315360000");
 });

packages/workers-response-store/README.md

@@ -74,7 +74,9 @@ The complete pair lives in `example/service-binding`: `cache-worker.ts` owns the
 
 ## API and storage model
 
-The library exposes `fetch`, `put`, `refresh({ tags, pathPrefixes })`, and `purge({ tags, pathPrefixes, purgeEverything })`. Cache identity is the request pathname plus query string. Response bodies live only in revision-specific R2 objects; SQLite stores metadata, freshness, revalidator descriptors, tag invalidation timestamps, and the reverse tag-to-entry index needed by refresh and purge.
+The library exposes `fetch`, `put`, `refresh({ tags, pathPrefixes })`, and `purge({ tags, pathPrefixes, purgeEverything })`. Cache identity is the request pathname plus query string. Response bodies live only in revision-specific R2 objects; SQLite stores metadata, freshness, revalidator descriptors, and tag invalidation timestamps. Explicit refresh and purge operations scan stored entry metadata instead of maintaining a write-heavy tag index.
+
+Framework soft-tag checks query their expiration only after a candidate cache hit and memoize each distinct tag set within the current request. Misses and repeated lookups therefore add no metadata DO request, while every check still reads the authoritative invalidation state directly.
 
 SQLite assigns monotonically increasing revisions and conditionally publishes metadata, so slow writes cannot replace newer writes or resurrect purged entries. User RPC, R2, and purge I/O happen outside SQLite transactions. Stale R2 responses within their SWR window return immediately while `ctx.waitUntil()` runs one claimed regeneration; hard-expired responses are never returned.
 

packages/workers-response-store/example/service-binding/user-worker.ts

@@ -104,6 +104,11 @@ export default {
         return json(await responseStore.purge((await request.json()) as ResponseStorePurgeOptions));
       }
 
+      if (request.method === "POST" && url.pathname === "/admin/tag-expiration") {
+        const { tags } = (await request.json()) as { tags: string[] };
+        return json({ expiration: await responseStore.getTagExpiration(tags) });
+      }
+
       return new Response("Not found", { status: 404 });
     } catch (error) {
       return json({ error: error instanceof Error ? error.message : String(error) }, 500);

packages/workers-response-store/example/worker.ts

@@ -62,6 +62,13 @@ async function handlePut(request: Request, store: WorkersResponseStore): Promise
   if (cdnCacheControl) headers.set("CDN-Cache-Control", cdnCacheControl);
 
   let body = request.body;
+  if (request.headers.get("X-Body-Failure") === "1") {
+    body = new ReadableStream({
+      start(controller) {
+        controller.error(new Error("Fixture body failure"));
+      },
+    });
+  }
   if (body && bodyDelayMs > 0) {
     const reader = body.getReader();
     let delayed = false;
@@ -82,6 +89,10 @@ async function handlePut(request: Request, store: WorkersResponseStore): Promise
       },
     });
   }
+  let teeSibling: ReadableStream | undefined;
+  if (body && request.headers.get("X-Tee-Body") === "1") {
+    [body, teeSibling] = body.tee();
+  }
 
   const response = new Response(NULL_BODY_STATUSES.has(status) ? null : body, {
     status,
@@ -99,9 +110,11 @@ async function handlePut(request: Request, store: WorkersResponseStore): Promise
         };
 
   const result = await store.put(target, response, {
+    coalesce: request.headers.get("X-Coalesce") === "1",
     revalidator,
     purgeExisting: request.headers.get("X-Purge-Existing") === "1",
   });
+  await new Response(teeSibling).arrayBuffer();
 
   return json(result);
 }
@@ -188,6 +201,11 @@ export default {
         return json(await responseStore.purge(options));
       }
 
+      if (request.method === "POST" && url.pathname === "/admin/tag-expiration") {
+        const { tags } = (await request.json()) as { tags: string[] };
+        return json({ expiration: await responseStore.getTagExpiration(tags) });
+      }
+
       if (request.method === "GET" && url.pathname === "/admin/stats") {
         return json({ regenerationCount });
       }