perf: bound relay background concurrency to 3

Replaces unbounded `Promise.all(relays.map(...))` calls with `pMap` using a concurrency limit of 3 for background operations like history hydration, metadata fetching, and DM sending.
This prevents network saturation and potential main-thread jank when many relays are configured.
Includes benchmark verification script `benchmarks/relay_concurrency_repro.mjs`.
Audited upload docs and confirmed accuracy.

Co-authored-by: PR0M3TH3AN <[email protected]>

CONTEXT.md

@@ -0,0 +1,29 @@
+# Context
+
+## Goal
+Improve app responsiveness by identifying and remediating background CPU/network work that degrades UX, while ensuring user-facing docs (/content) reflect the actual runtime behavior of upload/contribution flows.
+
+## Scope
+- Repository: `PR0M3TH3AN/bitvid` (unstable branch)
+- Focus Areas:
+    - P0: Login/auth, relay initialization & profile hydration, decryption of user lists.
+    - P1: Initial UI responsiveness (profile cache, relay load).
+    - P2: Background features (WebTorrent).
+    - Docs: `/content` (upload/contribution flows).
+
+## Assumptions
+- The codebase uses vanilla JS/ES modules.
+- `js/utils/logger.js` is the standard logging mechanism.
+- `js/constants.js` contains feature flags.
+- `config/instance-config.js` contains instance-specific config.
+
+## Constraints
+- Never invent files, APIs, libraries, or behaviors.
+- Prefer minimal incremental changes.
+- Keep build/tests green.
+- Security-critical changes require human signoff.
+
+## Definition of Done
+- Performance improvements are verified with metrics or manual tests.
+- Documentation updates are verified against code and runtime behavior.
+- PRs include `CONTEXT.md`, `TODO.md`, `DECISIONS.md`, `TEST_LOG.md`.

DECISIONS.md

@@ -0,0 +1,7 @@
+# Decisions
+
+## Log
+
+- **Bound Relay Concurrency**: Decided to use `pMap` with `RELAY_BACKGROUND_CONCURRENCY = 3` to limit concurrent relay requests during background tasks (history hydration, metadata fetch, DM send).
+  - *Rationale*: Unbounded `Promise.all` causes network congestion and can freeze the UI if many relays are configured. 3 is a conservative default.
+  - *Alternative*: Could have used a global queue, but per-operation concurrency is simpler and sufficient for now.

INITIAL_BASELINE.md

@@ -0,0 +1,10 @@
+# Initial Baseline
+
+## Metrics
+- Login time: TBD
+- Decrypt queue sizes: TBD
+- Relay latencies: TBD
+- Active WebTorrent clients: TBD
+
+## Observations
+- Initial scan pending.

TEST_LOG.md

@@ -0,0 +1,28 @@
+# Test Log
+
+## Environment
+- Branch: unstable
+- Node version: v22.22.0
+
+## Manual Verification
+
+### Benchmark: Relay Concurrency
+- Script: `benchmarks/relay_concurrency_repro.mjs`
+- Before: Unbounded (20 requests)
+- After: Bounded (3 requests)
+- Result: PASS
+
+### Unit Tests
+- Command: `npm run test:unit`
+- Result: PASS (13 tests passed in app-batch-fetch-profiles, etc., 12 tests passed in NostrClient)
+- Note: `nostr-tools` warning in benchmark is expected in Node env.
+
+## Docs Audit
+- Page: `content/docs/guides/upload-content.md`
+- Claims Verified:
+  - File types: Matches HTML accept attribute.
+  - Size limits: 2GB recommendation matches browser RAM constraints.
+  - Upload methods: Direct, External, Magnet supported.
+  - CORS: Automatic configuration verified in `js/services/s3Service.js`.
+  - HTTPS: Enforced in `js/services/videoNotePayload.js` and docs.
+- Result: No discrepancies found.

TODO.md

@@ -0,0 +1,11 @@
+# TODO
+
+- [ ] Run search patterns to identify performance bottlenecks.
+- [ ] Analyze search results and prioritize findings.
+- [ ] Select a P0/P1 issue to fix.
+- [ ] Create a reproduction/benchmark for the selected issue.
+- [ ] Implement the fix (small, safe, tested).
+- [ ] Verify the fix.
+- [ ] Audit `/content` upload docs.
+- [ ] Update `/content` if necessary.
+- [ ] Create daily report.

benchmarks/relay_concurrency_repro.mjs

@@ -0,0 +1,101 @@
+import { NostrClient } from "../js/nostr/client.js";
+import { pMap } from "../js/utils/asyncUtils.js";
+
+// Mock globals for Node environment
+globalThis.WebSocket = class MockWebSocket {};
+globalThis.localStorage = {
+  getItem: () => null,
+  setItem: () => {},
+  removeItem: () => {},
+  clear: () => {}
+};
+globalThis.indexedDB = {
+  open: () => ({
+    result: {
+      createObjectStore: () => {},
+      transaction: () => ({ objectStore: () => ({ get: () => {}, put: () => {} }) })
+    },
+    onupgradeneeded: () => {},
+    onsuccess: () => {}
+  })
+};
+
+// Mock dependencies
+class MockPool {
+  constructor() {
+    this.activeRequests = 0;
+    this.maxConcurrent = 0;
+  }
+
+  async list(relays, filters) {
+    this.activeRequests++;
+    if (this.activeRequests > this.maxConcurrent) {
+      this.maxConcurrent = this.activeRequests;
+    }
+
+    // Simulate network delay
+    await new Promise(resolve => setTimeout(resolve, 50));
+
+    this.activeRequests--;
+    return [];
+  }
+
+  async get(relays, filter) {
+    return null;
+  }
+}
+
+async function runBenchmark() {
+  console.log("Starting Relay Concurrency Benchmark...");
+
+  const client = new NostrClient();
+  const mockPool = new MockPool();
+  client.pool = mockPool;
+
+  // Simulate 20 relays
+  const relays = Array.from({ length: 20 }, (_, i) => `wss://relay${i}.example.com`);
+  client.relays = relays;
+  client.readRelays = relays;
+
+  // 1. Benchmark fetchAndCacheNip71Metadata
+  console.log("\nTesting fetchAndCacheNip71Metadata with 20 relays...");
+  mockPool.maxConcurrent = 0;
+
+  const pointerMap = new Map();
+  pointerMap.set("e:123", { type: "e", value: "123", relays: [] });
+
+  await client.fetchAndCacheNip71Metadata(pointerMap, ["e:123"]);
+
+  console.log(`Max concurrent requests: ${mockPool.maxConcurrent}`);
+  if (mockPool.maxConcurrent > 5) {
+    console.log("FAIL: Concurrency is unbounded!");
+  } else {
+    console.log("PASS: Concurrency is bounded.");
+  }
+
+  // 2. Benchmark hydrateVideoHistory
+  console.log("\nTesting hydrateVideoHistory with 20 relays...");
+  mockPool.maxConcurrent = 0;
+
+  const video = {
+    id: "v1",
+    videoRootId: "root1",
+    tags: [["d", "d1"]],
+    pubkey: "pub1"
+  };
+
+  // Prime local cache to force relay fetch
+  // We need to simulate that we found <= 1 version locally
+  client.allEvents.set("v1", video);
+
+  await client.hydrateVideoHistory(video);
+
+  console.log(`Max concurrent requests: ${mockPool.maxConcurrent}`);
+    if (mockPool.maxConcurrent > 5) {
+    console.log("FAIL: Concurrency is unbounded!");
+  } else {
+    console.log("PASS: Concurrency is bounded.");
+  }
+}
+
+runBenchmark().catch(console.error);

daily-perf-report-2026-02-08.md

@@ -0,0 +1,23 @@
+# Daily Performance Report - 2026-02-08
+
+**Summary:** Bounded background relay concurrency to 3 to prevent network saturation and UI freezes. Verified upload documentation accuracy.
+
+## Findings
+
+### P1: Unbounded Relay Concurrency
+- **Location:** `js/nostr/client.js` (`fetchAndCacheNip71Metadata`, `hydrateVideoHistory`, `_sendNip17DirectMessage`).
+- **Impact:** Simultaneously opening connections to all relays (could be 20+) caused network congestion and potential UI jank.
+- **Fix:** Implemented `pMap` with `RELAY_BACKGROUND_CONCURRENCY = 3`.
+- **Status:** Fixed.
+
+## Metrics
+- **Max Concurrent Relay Requests:** Reduced from N (number of relays) to 3.
+- **Login Time:** (Not measured directly today, but expected improvement due to reduced initial load).
+
+## Docs Audit
+- **Page:** `content/docs/guides/upload-content.md`
+- **Result:** Verified accurate. Matches code behavior for file types, size recommendations, and HTTPS enforcement.
+
+## Artifacts
+- [PR #1] perf: bound relay background concurrency
+- `benchmarks/relay_concurrency_repro.mjs` created.

js/nostr/client.js

@@ -135,7 +135,7 @@ import {
   summarizeDmEventForLog,
 } from "./dmDecryptDiagnostics.js";
 import { devLogger, userLogger } from "../utils/logger.js";
-import { withRequestTimeout } from "../utils/asyncUtils.js";
+import { withRequestTimeout, pMap } from "../utils/asyncUtils.js";
 import { LRUCache } from "../utils/lruCache.js";
 import { updateConversationFromMessage, writeMessages } from "../storage/dmDb.js";
 import {
@@ -287,6 +287,7 @@ import {
   RELAY_FAILURE_WINDOW_MS,
   RELAY_FAILURE_WINDOW_THRESHOLD,
   RELAY_SUMMARY_LOG_INTERVAL_MS,
+  RELAY_BACKGROUND_CONCURRENCY,
 } from "./relayConstants.js";
 const EVENTS_CACHE_STORAGE_KEY = "bitvid:eventsCache:v1";
 // We use the policy TTL, but currently the storage backend is hardcoded to IDB (with localStorage fallback).
@@ -1867,10 +1868,10 @@ export class NostrClient {
         devLogger.warn("[nostr] Failed to persist outgoing DM.", error);
       }
 
-      const recipientPublishResults = await Promise.all(
-        recipientSelection.relays.map((url) =>
-          publishEventToRelay(this.pool, url, recipientGiftWrap.wrap),
-        ),
+      const recipientPublishResults = await pMap(
+        recipientSelection.relays,
+        (url) => publishEventToRelay(this.pool, url, recipientGiftWrap.wrap),
+        { concurrency: RELAY_BACKGROUND_CONCURRENCY },
       );
 
       const recipientSuccess = recipientPublishResults.some(
@@ -1901,10 +1902,10 @@ export class NostrClient {
       }
 
       if (senderGiftWrap && senderRelayTargets.length) {
-        const senderPublishResults = await Promise.all(
-          senderRelayTargets.map((url) =>
-            publishEventToRelay(this.pool, url, senderGiftWrap.wrap),
-          ),
+        const senderPublishResults = await pMap(
+          senderRelayTargets,
+          (url) => publishEventToRelay(this.pool, url, senderGiftWrap.wrap),
+          { concurrency: RELAY_BACKGROUND_CONCURRENCY },
         );
         if (!senderPublishResults.some((result) => result.success)) {
           devLogger.warn("[nostr] Failed to publish sender copy of NIP-17 DM.", {
@@ -2119,8 +2120,10 @@ export class NostrClient {
 
     const relays = recipientRelays.length ? recipientRelays : fallbackRelays;
 
-    const publishResults = await Promise.all(
-      relays.map((url) => publishEventToRelay(this.pool, url, signedEvent))
+    const publishResults = await pMap(
+      relays,
+      (url) => publishEventToRelay(this.pool, url, signedEvent),
+      { concurrency: RELAY_BACKGROUND_CONCURRENCY },
     );
 
     const success = publishResults.some((result) => result.success);
@@ -3358,8 +3361,9 @@ export class NostrClient {
     };
 
     try {
-      const responses = await Promise.all(
-        this.relays.map(async (url) => {
+      const responses = await pMap(
+        this.relays,
+        async (url) => {
           try {
             const events = await this.pool.list([url], [filter]);
             return Array.isArray(events) ? events : [];
@@ -3370,7 +3374,8 @@ export class NostrClient {
             );
             return [];
           }
-        }),
+        },
+        { concurrency: RELAY_BACKGROUND_CONCURRENCY },
       );
 
       const deduped = new Map();
@@ -3882,8 +3887,9 @@ export class NostrClient {
       }
 
       try {
-        const perRelay = await Promise.all(
-          this.getHealthyRelays(this.relays).map(async (url) => {
+        const perRelay = await pMap(
+          this.getHealthyRelays(this.relays),
+          async (url) => {
             try {
               const events = await this.pool.list([url], [filter]);
               return events || [];
@@ -3894,7 +3900,8 @@ export class NostrClient {
               );
               return [];
             }
-          })
+          },
+          { concurrency: RELAY_BACKGROUND_CONCURRENCY },
         );
 
         const merged = perRelay.flat();

js/nostr/relayConstants.js

@@ -22,3 +22,4 @@ export const RELAY_CIRCUIT_BREAKER_COOLDOWN_MS = TEN_MINUTES_MS;
 export const RELAY_FAILURE_WINDOW_MS = FIVE_MINUTES_MS;
 export const RELAY_FAILURE_WINDOW_THRESHOLD = 3;
 export const RELAY_SUMMARY_LOG_INTERVAL_MS = MEDIUM_TIMEOUT_MS;
+export const RELAY_BACKGROUND_CONCURRENCY = 3;