improve stability

2026-09-13 12:02:27 +02:00
parent 862f73d26d
commit 8400bd5b3a
8 changed files with 426 additions and 140 deletions
@@ -11,8 +11,9 @@ import { performanceMetrics } from '../metrics/PerformanceMetrics.js';
 import { UnifiedProcessingStateManager } from '../logic/UnifiedProcessingStateManager.js';
 import type { IKVClient } from '../kv/IKVClient.js';
 import type { KVManager } from '../kv/KVManager.js';
-import type { ExtendedProcessingSnapshot, IKVClientWithPubSub } from '../types/ExtendedInterfaces.js';
-import { getErrorMessage } from '../types/ExtendedInterfaces.js';
+import type { ExtendedProcessingSnapshot } from '../types/ExtendedInterfaces.js';
+import { getErrorMessage, hasFileTuples } from '../types/ExtendedInterfaces.js';
+import type { IKVClientWithFileTuples } from '../types/ExtendedInterfaces.js';
 import { config } from '../config/EnvConfig.js';
 import * as webdav from '../webdav/WebdavClient.js';
 import type { PluginManager } from '../plugin-engine/PluginManager.js';
@@ -29,6 +30,45 @@ export interface UnifiedAPIServerConfig {
  enableCors?: boolean;
 }

+/** File totals served by /api/stats. Null when meta-core cannot supply them. */
+interface FileStats {
+  fileCount: number | null;
+  totalSize: number | null;
+  source: 'meta-core' | 'unavailable';
+}
+
+/** Metadata reads in flight at once while a recompute builds its task list. */
+const RECOMPUTE_READ_CONCURRENCY = 8;
+
+/** Run `worker` over `items` with at most `limit` calls in flight. */
+async function forEachWithConcurrency<T>(
+  items: readonly T[],
+  limit: number,
+  worker: (item: T) => Promise<void>
+): Promise<void> {
+  let next = 0;
+  const runners = Array.from({ length: Math.min(limit, items.length) }, async () => {
+    while (next < items.length) {
+      const item = items[next++];
+      await worker(item);
+    }
+  });
+  await Promise.all(runners);
+}
+
+/** Flatten nested metadata into the `a/b/c` keys the task scheduler expects. */
+function flattenMetadata(obj: Record<string, unknown>, out: Record<string, string> = {}, prefix = ''): Record<string, string> {
+  for (const [key, value] of Object.entries(obj)) {
+    const fullKey = prefix ? `${prefix}/${key}` : key;
+    if (value !== null && typeof value === 'object' && !Array.isArray(value)) {
+      flattenMetadata(value as Record<string, unknown>, out, fullKey);
+    } else if (value !== undefined && value !== null) {
+      out[fullKey] = String(value);
+    }
+  }
+  return out;
+}
+
 export class UnifiedAPIServer {
  private app: FastifyInstance;
  private unifiedStateManager: UnifiedProcessingStateManager | null = null;
@@ -44,9 +84,15 @@ export class UnifiedAPIServer {
  private containerPluginScheduler: ContainerPluginScheduler | null = null;
  private streamingPipeline: StreamingPipeline | null = null;

-  // Cache for total file size (avoid running du on every request)
-  private totalSizeCache: { value: number; timestamp: number } | null = null;
-  private static TOTAL_SIZE_CACHE_TTL_MS = 30000; // 30 seconds
+  // /api/stats file totals: stale-while-revalidate, one refresh at a time.
+  // Never walk hashIds for these — on a shared meta-core that is every gateway
+  // record too (82k on watch.nsl.sh), and a sweep per poll stacked unbounded.
+  private fileStats: { value: FileStats; fetchedAt: number } | null = null;
+  private fileStatsInFlight: Promise<FileStats> | null = null;
+  private static FILE_STATS_TTL_MS = 30000; // 30 seconds
+
+  // Plugins whose recompute is currently being queued (single-flight per plugin)
+  private recomputeInFlight = new Set<string>();

  constructor(
    config: UnifiedAPIServerConfig = {},
@@ -97,48 +143,46 @@ export class UnifiedAPIServer {
  }

  /**
-   * Get total size of processed files from Redis sizeByte field (cached)
-   * This is "eventually correct" - accumulates as files are processed by the file-info plugin
+   * File count + total size of the files meta-core holds on disk, for the
+   * monitor's "Total Size" card: one summary call to meta-core's
+   * GET /api/files/tuples (batched server-side), cached for FILE_STATS_TTL_MS.
+   *
+   * Stale-while-revalidate with a single in-flight refresh — a poll never waits
+   * on meta-core once a value exists, and concurrent polls share one request.
   */
-  private async getTotalFileSizeFromRedis(): Promise<number> {
-    // Check cache
-    const now = Date.now();
-    if (this.totalSizeCache && (now - this.totalSizeCache.timestamp) < UnifiedAPIServer.TOTAL_SIZE_CACHE_TTL_MS) {
-      return this.totalSizeCache.value;
+  private async getFileStats(): Promise<FileStats> {
+    const cached = this.fileStats;
+    if (cached && Date.now() - cached.fetchedAt < UnifiedAPIServer.FILE_STATS_TTL_MS) {
+      return cached.value;
    }

-    // Sum sizeByte from all file entries in Redis
-    let totalSize = 0;
-
-    if (!this.kvClient) {
-      return 0;
+    if (!this.fileStatsInFlight) {
+      this.fileStatsInFlight = this.fetchFileStats()
+        .catch((error: unknown): FileStats => {
+          console.warn('[API] /api/stats: meta-core file totals unavailable:', getErrorMessage(error));
+          return cached?.value ?? { fileCount: null, totalSize: null, source: 'unavailable' };
+        })
+        .then((value) => {
+          this.fileStats = { value, fetchedAt: Date.now() };
+          return value;
+        })
+        .finally(() => {
+          this.fileStatsInFlight = null;
+        });
    }

-    try {
-      // Get all file hash IDs
-      const hashIds = await this.kvClient.getAllHashIds();
+    return cached ? cached.value : this.fileStatsInFlight;
+  }

-      // Sum up sizeByte values (batch process for efficiency)
-      for (const hashId of hashIds) {
-        try {
-          const sizeByte = await this.kvClient.getMetadata(hashId, 'sizeByte');
-          if (sizeByte !== null && sizeByte !== undefined) {
-            const size = typeof sizeByte === 'number' ? sizeByte : parseInt(String(sizeByte), 10);
-            if (!isNaN(size) && size > 0) {
-              totalSize += size;
-            }
-          }
-        } catch {
-          // Skip entries without sizeByte
-        }
-      }
-    } catch (error) {
-      console.warn('[API] Failed to calculate total size from Redis:', error);
+  private async fetchFileStats(): Promise<FileStats> {
+    if (!this.kvClient || !hasFileTuples(this.kvClient)) {
+      return { fileCount: null, totalSize: null, source: 'unavailable' };
    }
-
-    // Update cache
-    this.totalSizeCache = { value: totalSize, timestamp: now };
-    return totalSize;
+    const summary = await this.kvClient.getFileTuples({ summary: true });
+    if (!summary) {
+      return { fileCount: null, totalSize: null, source: 'unavailable' };
+    }
+    return { fileCount: summary.count, totalSize: summary.totalSize, source: 'meta-core' };
  }

  /**
@@ -524,53 +568,17 @@ export class UnifiedAPIServer {


  /**
-   * Setup Stats API routes (Redis stats for monitor UI)
+   * Setup Stats API routes (file totals for the monitor UI)
   */
  private setupStatsRoutes(): void {
    if (!this.kvClient) {
      return;
    }

-    // Get Redis/KV stats (for monitor UI)
-    this.app.get('/api/stats', async (request, reply) => {
-      try {
-        const hashIds = await this.kvClient!.getAllHashIds();
-        const redis = (this.kvClient as IKVClientWithPubSub).getRedisClient?.() as { info: (section: string) => Promise<string> } | undefined;
-
-        let memoryUsage = 'N/A';
-        let memoryUsageBytes = 0;
-        if (redis) {
-          try {
-            const info = await redis.info('memory');
-            const match = info.match(/used_memory_human:(\S+)/);
-            const bytesMatch = info.match(/used_memory:(\d+)/);
-            if (match) {
-              memoryUsage = match[1];
-            }
-            if (bytesMatch) {
-              memoryUsageBytes = parseInt(bytesMatch[1], 10);
-            }
-          } catch {
-            // Ignore memory info errors
-          }
-        }
-
-        // Get total size from Redis sizeByte (eventually correct as files are processed)
-        const totalSize = await this.getTotalFileSizeFromRedis();
-
-        return {
-          fileCount: hashIds.length,
-          keyCount: hashIds.length,
-          totalSize,
-          memoryUsage,
-          memoryUsageBytes
-        };
-      } catch (error: any) {
-        return reply.status(500).send({
-          error: 'Failed to get stats',
-          details: error.message
-        });
-      }
+    // At most one meta-core call per FILE_STATS_TTL_MS however often the
+    // monitor polls — see getFileStats.
+    this.app.get('/api/stats', async () => {
+      return this.getFileStats();
    });
  }

@@ -886,38 +894,43 @@ export class UnifiedAPIServer {
        return reply.status(400).send({ error: `Plugin '${pluginId}' is not active` });
      }

+      if (!hasFileTuples(this.kvClient)) {
+        return reply.status(501).send({ error: 'Recompute needs meta-core GET /api/files/tuples' });
+      }
+      const kvClient = this.kvClient as IKVClientWithFileTuples;
+
+      if (this.recomputeInFlight.has(pluginId)) {
+        return reply.status(409).send({ error: `Recompute for plugin '${pluginId}' is already being queued` });
+      }
+
+      this.recomputeInFlight.add(pluginId);
      try {
-        // Get all files from KV
-        const hashIds = await this.kvClient.getAllHashIds();
-        console.log(`[Recompute] Starting recompute for plugin '${pluginId}' on ${hashIds.length} files`);
+        // Only file-backed records can be recomputed, and meta-core lists exactly
+        // those in one batched call. Walking getAllHashIds() instead reads every
+        // gateway record too (82k on watch.nsl.sh) to keep a few thousand.
+        const tuples = await kvClient.getFileTuples();
+        if (!tuples || !tuples.files) {
+          return reply.status(501).send({
+            error: 'Recompute needs meta-core GET /api/files/tuples',
+            details: 'meta-core did not return a file list'
+          });
+        }
+        const candidates = tuples.files;
+        console.log(`[Recompute] Starting recompute for plugin '${pluginId}' on ${candidates.length} files`);

        // Prepare file data with metadata for TaskScheduler
        const files: Array<{ filePath: string; fileHash: string; kvData?: Record<string, string> }> = [];
-
-        for (const hashId of hashIds) {
-          const metadata = await this.kvClient.getMetadataFlat(hashId);
-          if (metadata && metadata.filePath) {
-            // Convert nested metadata to flat key-value pairs for KVStore
-            const kvData: Record<string, string> = {};
-            const flattenObj = (obj: any, prefix = '') => {
-              for (const [key, value] of Object.entries(obj)) {
-                const fullKey = prefix ? `${prefix}/${key}` : key;
-                if (value !== null && typeof value === 'object' && !Array.isArray(value)) {
-                  flattenObj(value, fullKey);
-                } else if (value !== undefined && value !== null) {
-                  kvData[fullKey] = String(value);
-                }
-              }
-            };
-            flattenObj(metadata);
-
-            files.push({
-              fileHash: hashId,
-              filePath: metadata.filePath,
-              kvData
-            });
+        await forEachWithConcurrency(candidates, RECOMPUTE_READ_CONCURRENCY, async (tuple) => {
+          const metadata = await kvClient.getMetadataFlat(tuple.hashId);
+          if (!metadata) {
+            return;
          }
-        }
+          files.push({
+            fileHash: tuple.hashId,
+            filePath: metadata.filePath || tuple.filePath,
+            kvData: flattenMetadata(metadata)
+          });
+        });

        // Create and enqueue tasks with forceRecompute option
        const tasks = taskScheduler.createTasksForPluginOnFiles(
@@ -935,7 +948,7 @@ export class UnifiedAPIServer {
          status: 'ok',
          message: `Recompute triggered for plugin '${pluginId}'`,
          filesQueued: tasks.length,
-          totalFiles: hashIds.length
+          totalFiles: candidates.length
        };
      } catch (error: any) {
        console.error(`[Recompute] Error triggering recompute for plugin '${pluginId}':`, error);
@@ -943,6 +956,8 @@ export class UnifiedAPIServer {
          error: 'Failed to trigger recompute',
          details: error.message
        });
+      } finally {
+        this.recomputeInFlight.delete(pluginId);
      }
    });
  }
@@ -8,6 +8,7 @@
 import { expect } from 'chai';
 import { UnifiedAPIServer } from './UnifiedAPIServer.js';
 import { UnifiedProcessingStateManager } from '../logic/UnifiedProcessingStateManager.js';
+import { performanceMetrics } from '../metrics/PerformanceMetrics.js';
 import type { IKVClient } from '../kv/IKVClient.js';
 import type { FastifyInstance } from 'fastify';

@@ -23,6 +24,25 @@ class MockKVClient implements IKVClient {
    private data: Map<string, Map<string, any>> = new Map();
    private rawStore: Map<string, string> = new Map();

+    // Stand-in for meta-core's GET /api/files/tuples. null = a meta-core that
+    // predates the endpoint.
+    fileTuples: Array<{ hashId: string; filePath: string; sizeByte: number; mtimeNano: number }> | null = null;
+    fileTuplesDelayMs = 0;
+    calls = { getFileTuples: 0, getAllHashIds: 0, getMetadataFlat: 0 };
+
+    async getFileTuples(opts: { summary?: boolean } = {}) {
+        this.calls.getFileTuples++;
+        if (this.fileTuplesDelayMs) {
+            await new Promise(resolve => setTimeout(resolve, this.fileTuplesDelayMs));
+        }
+        if (!this.fileTuples) return null;
+        const files = this.fileTuples;
+        const totalSize = files.reduce((sum, f) => sum + f.sizeByte, 0);
+        return opts.summary
+            ? { count: files.length, totalSize }
+            : { count: files.length, totalSize, files };
+    }
+
    // Basic operations
    async set(key: string, value: any): Promise<void> {
        this.rawStore.set(key, JSON.stringify(value));
@@ -99,6 +119,7 @@ class MockKVClient implements IKVClient {
    }

    async getMetadataFlat(hashId: string): Promise<any | null> {
+        this.calls.getMetadataFlat++;
        const entry = this.data.get(hashId);
        if (!entry) return null;
        return Object.fromEntries(entry);
@@ -125,6 +146,7 @@ class MockKVClient implements IKVClient {
    }

    async getAllHashIds(): Promise<string[]> {
+        this.calls.getAllHashIds++;
        return Array.from(this.data.keys());
    }

@@ -736,3 +758,157 @@ describe('UnifiedAPIServer', function() {
        });
    });
 });
+
+// =============================================================================
+// File totals + recompute against meta-core's GET /api/files/tuples
+// =============================================================================
+//
+// Each test builds its own server: /api/stats caches for 30 s and recompute is
+// single-flight, so shared state between tests would hide both behaviours.
+
+describe('UnifiedAPIServer file totals and recompute', function() {
+    const tuple = (hashId: string, sizeByte: number) =>
+        ({ hashId, filePath: `/files/watch/${hashId}.mkv`, sizeByte, mtimeNano: 1 });
+
+    let app: FastifyInstance;
+    let kv: MockKVClient;
+    let queued: Array<{ pluginId: string; fileHash: string }>;
+
+    beforeEach(async function() {
+        kv = new MockKVClient();
+        queued = [];
+        const pluginManager = { getPlugins: () => [{ id: 'ffmpeg', active: true }] };
+        const taskScheduler = {
+            createTasksForPluginOnFiles: (pluginId: string, files: Array<{ fileHash: string }>) =>
+                files.map(f => ({ pluginId, fileHash: f.fileHash })),
+            enqueueTasks: (tasks: Array<{ pluginId: string; fileHash: string }>) => { queued.push(...tasks); },
+        };
+        const server = new UnifiedAPIServer(
+            { port: 0, host: 'localhost', enableCors: false },
+            new MockProcessingStateManager() as any,
+            kv as any,
+            4,
+            16,
+            () => ({ fast: { pending: 0, running: 0 }, background: { pending: 0, running: 0 } }),
+            undefined,
+            () => pluginManager as any,
+            () => taskScheduler as any
+        );
+        app = server.getApp();
+        await app.ready();
+    });
+
+    afterEach(async function() {
+        await app.close();
+    });
+
+    it('GET /api/stats sums meta-core file tuples without walking hash ids', async function() {
+        kv.fileTuples = [tuple('a', 100), tuple('b', 250)];
+
+        const response = await app.inject({ method: 'GET', url: '/api/stats' });
+
+        expect(response.statusCode).to.equal(200);
+        expect(JSON.parse(response.payload)).to.deep.equal({ fileCount: 2, totalSize: 350, source: 'meta-core' });
+        expect(kv.calls.getAllHashIds).to.equal(0);
+        expect(kv.calls.getMetadataFlat).to.equal(0);
+    });
+
+    it('GET /api/stats degrades to nulls on a meta-core without the endpoint', async function() {
+        kv.fileTuples = null;
+
+        const response = await app.inject({ method: 'GET', url: '/api/stats' });
+
+        expect(response.statusCode).to.equal(200);
+        expect(JSON.parse(response.payload)).to.deep.equal({ fileCount: null, totalSize: null, source: 'unavailable' });
+        expect(kv.calls.getAllHashIds).to.equal(0);
+    });
+
+    it('GET /api/stats shares one meta-core call between concurrent polls', async function() {
+        kv.fileTuples = [tuple('a', 100)];
+        kv.fileTuplesDelayMs = 50;
+
+        const responses = await Promise.all(
+            Array.from({ length: 10 }, () => app.inject({ method: 'GET', url: '/api/stats' }))
+        );
+
+        for (const response of responses) {
+            expect(response.statusCode).to.equal(200);
+            expect(JSON.parse(response.payload).totalSize).to.equal(100);
+        }
+        expect(kv.calls.getFileTuples).to.equal(1);
+    });
+
+    it('POST recompute returns 501 on a meta-core without the endpoint', async function() {
+        kv.fileTuples = null;
+
+        const response = await app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' });
+
+        expect(response.statusCode).to.equal(501);
+        expect(kv.calls.getAllHashIds).to.equal(0);
+        expect(queued).to.have.length(0);
+    });
+
+    it('POST recompute queues only file-backed records', async function() {
+        kv.seedData('a', { filePath: '/files/watch/a.mkv', fileType: 'video' });
+        kv.seedData('b', { filePath: '/files/watch/b.mkv', fileType: 'video' });
+        kv.seedData('gateway-record', { title: 'Not a file' });
+        kv.fileTuples = [tuple('a', 100), tuple('b', 250)];
+
+        const response = await app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' });
+
+        expect(response.statusCode).to.equal(200);
+        const body = JSON.parse(response.payload);
+        expect(body.filesQueued).to.equal(2);
+        expect(body.totalFiles).to.equal(2);
+        expect(queued.map(q => q.fileHash).sort()).to.deep.equal(['a', 'b']);
+        expect(kv.calls.getMetadataFlat).to.equal(2);
+        expect(kv.calls.getAllHashIds).to.equal(0);
+    });
+
+    it('POST recompute refuses a second run for the same plugin while one is queuing', async function() {
+        kv.seedData('a', { filePath: '/files/watch/a.mkv' });
+        kv.fileTuples = [tuple('a', 100)];
+        kv.fileTuplesDelayMs = 50;
+
+        const [first, second] = await Promise.all([
+            app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' }),
+            app.inject({ method: 'POST', url: '/api/plugins/ffmpeg/recompute' }),
+        ]);
+
+        expect([first.statusCode, second.statusCode].sort()).to.deep.equal([200, 409]);
+        expect(queued).to.have.length(1);
+    });
+});
+
+// =============================================================================
+// File-level processing metric
+// =============================================================================
+
+describe('UnifiedProcessingStateManager file metric', function() {
+    // Files announced over SSE go straight to light processing; they are never
+    // marked discovered, which is the path that used to leave "Processed" at 0.
+    const runFile = (manager: UnifiedProcessingStateManager, filePath: string, error?: string) => {
+        manager.startLightProcessing(filePath);
+        manager.completeLightProcessing(filePath, 'bagacbabaeexamplehash');
+        manager.startHashProcessing(filePath);
+        manager.completeHashProcessing(filePath, 'bagacbabaeexamplehash', undefined, error);
+    };
+
+    it('counts a file as processed when its hash phase completes cleanly', function() {
+        const manager = new UnifiedProcessingStateManager();
+        const before = performanceMetrics.getMetrics().totalFilesProcessed;
+
+        runFile(manager, '/files/watch/metric-ok.mkv');
+
+        expect(performanceMetrics.getMetrics().totalFilesProcessed).to.equal(before + 1);
+    });
+
+    it('does not count a file whose hash phase failed', function() {
+        const manager = new UnifiedProcessingStateManager();
+        const before = performanceMetrics.getMetrics().totalFilesProcessed;
+
+        runFile(manager, '/files/watch/metric-failed.mkv', 'plugin failed');
+
+        expect(performanceMetrics.getMetrics().totalFilesProcessed).to.equal(before);
+    });
+});
@@ -19,6 +19,24 @@ import {
    buildFilePrefix,
 } from './MetadataUtils.js';

+/** One file-backed root as listed by meta-core's GET /api/files/tuples. */
+export interface FileTuple {
+    hashId: string;
+    filePath: string;
+    sizeByte: number;
+    mtimeNano: number;
+}
+
+/**
+ * GET /api/files/tuples body. `files` is present unless the summary form was
+ * asked for.
+ */
+export interface FileTuplesResult {
+    count: number;
+    totalSize: number;
+    files?: FileTuple[];
+}
+
 export interface MetaCoreApiWriterConfig {
    /** Base URL for meta-core's HTTP API (e.g. http://metacore-app:9000) */
    apiUrl: string;
@@ -139,6 +157,27 @@ export class MetaCoreApiWriter {
        return Array.isArray(ids) ? ids : [];
    }

+    /**
+     * GET /api/files/tuples. meta-core's FILE-BACKED roots (records carrying
+     * filePath, sizeByte and mtimeNano) with sizes, read server-side in batched
+     * MGETs — the cheap alternative to walking getAllHashIds(), which on a
+     * shared meta-core is every gateway record too. `summary` omits the rows.
+     *
+     * Returns null when meta-core predates the endpoint (404, or a body that is
+     * not the expected JSON).
+     */
+    async getFileTuples(opts: { summary?: boolean } = {}): Promise<FileTuplesResult | null> {
+        const path = opts.summary ? '/api/files/tuples?summary=1' : '/api/files/tuples';
+        const body = await this.fetchJsonAllowing404('GET', path);
+        if (!body || typeof body !== 'object') return null;
+        const b = body as { count?: unknown; totalSize?: unknown; files?: unknown };
+        return {
+            count: Number(b.count) || 0,
+            totalSize: Number(b.totalSize) || 0,
+            files: Array.isArray(b.files) ? (b.files as FileTuple[]) : undefined,
+        };
+    }
+
    /**
     * GET /health on meta-core. Used as a write-path health probe.
     */
@@ -21,7 +21,7 @@ import {
    buildFilePrefix,
    buildPropertyKey,
 } from './MetadataUtils.js';
-import { MetaCoreApiWriter } from './MetaCoreApiWriter.js';
+import { MetaCoreApiWriter, type FileTuplesResult } from './MetaCoreApiWriter.js';

 // ESM/CJS interop for ioredis
 const Redis = (IORedis as any).default ?? IORedis;
@@ -102,7 +102,22 @@ export class RedisKVClient implements IKVClient {
            // automatic connect. Any caller that tries to use the Redis
            // path (e.g. unmigrated stream code) will fail loudly rather
            // than silently misbehaving.
-            this.redis = new Redis({ host: '127.0.0.1', port: 0, lazyConnect: true, enableOfflineQueue: false });
+            this.redis = new Redis({
+                host: '127.0.0.1',
+                port: 0,
+                lazyConnect: true,
+                enableOfflineQueue: false,
+                // Never reconnect. A stub that retries turns one stray call into
+                // an endless "Unhandled error event: ECONNREFUSED" loop.
+                retryStrategy: () => null,
+                maxRetriesPerRequest: 0,
+            });
+            let stubWarned = false;
+            this.redis.on('error', (err: Error) => {
+                if (stubWarned) return;
+                stubWarned = true;
+                console.warn(`[Redis] HTTP-only stub was used and refused (${err.message}) — a caller still reaches for direct Redis`);
+            });
            this.isConnected = false;
            console.log('[Redis] HTTP-only mode — no direct Redis connection');
            return;
@@ -474,6 +489,15 @@ export class RedisKVClient implements IKVClient {
        return await this.redis.smembers(indexKey);
    }

+    /**
+     * File-backed roots from meta-core (GET /api/files/tuples). Only the HTTP
+     * writer can serve this; direct-Redis mode returns null so callers take
+     * their degraded path instead of sweeping every record.
+     */
+    async getFileTuples(opts: { summary?: boolean } = {}): Promise<FileTuplesResult | null> {
+        return this.writer ? this.writer.getFileTuples(opts) : null;
+    }
+
    // ========================================================================
    // Pub/Sub Operations
    // ========================================================================
@@ -195,6 +195,16 @@ export class UnifiedProcessingStateManager {
      performanceMetrics.recordHashProcessing(hashProcessingTime);
    }

+    // File-level metric, one per file that finished cleanly. Nothing recorded
+    // it before, so the monitor's "Processed" tile stayed at 0. Files announced
+    // over SSE are never marked discovered, so fall back to the light phase.
+    if (!error) {
+      const fileTime = totalProcessingTime
+        ?? (hashState?.lightProcessingStartedAt !== undefined ? now - hashState.lightProcessingStartedAt : hashProcessingTime)
+        ?? 0;
+      performanceMetrics.recordFileProcessing(filePath, fileTime);
+    }
+
    const doneState: UnifiedFileState = {
      filePath,
      state: 'done',
@@ -8,6 +8,7 @@

 import type { HashMeta } from '@metazla/meta-interface';
 import type { IKVClient } from '../kv/IKVClient.js';
+import type { FileTuplesResult } from '../kv/MetaCoreApiWriter.js';
 import type { FileAnalyzerInterface } from '../logic/fileProcessor/FileAnalyzerInterface.js';
 import type { ContainerTask } from '../container-plugins/types.js';
 import type { UnifiedProcessingSnapshot } from '../logic/UnifiedProcessingStateManager.js';
@@ -41,6 +42,21 @@ export function hasPublish(client: IKVClient): client is IKVClientWithPubSub {
    return typeof (client as IKVClientWithPubSub).publish === 'function';
 }

+/**
+ * IKVClient that can list meta-core's file-backed roots in one call
+ * (GET /api/files/tuples). Resolves null when meta-core predates the endpoint.
+ */
+export interface IKVClientWithFileTuples extends IKVClient {
+    getFileTuples(opts?: { summary?: boolean }): Promise<FileTuplesResult | null>;
+}
+
+/**
+ * Type guard to check if a KVClient can list file-backed roots
+ */
+export function hasFileTuples(client: IKVClient): client is IKVClientWithFileTuples {
+    return typeof (client as IKVClientWithFileTuples).getFileTuples === 'function';
+}
+
 /**
 * IKVClient with Redis Streams capabilities
 *
@@ -1,4 +1,4 @@
-import { useState, useEffect, useCallback } from 'react';
+import { useState, useEffect, useCallback, useRef } from 'react';
 import {
    ProcessingStatus,
    Metrics,
@@ -60,29 +60,35 @@ function Monitor() {
    const [failedFiles, setFailedFiles] = useState<FailedFile[]>([]);
    const [showPipelineHelp, setShowPipelineHelp] = useState(false);

-    const fetchData = useCallback(async () => {
-        try {
-            const [statusRes, metricsRes, queueRes, statsRes, failedRes] = await Promise.all([
-                fetch('/api/processing/status'),
-                fetch('/api/metrics'),
-                fetch('/api/processing/queue'),
-                fetch('/api/stats'),
-                fetch('/api/processing/failed')
-            ]);
+    // Each endpoint renders as soon as it answers, so one slow or failing call
+    // cannot blank the page. A tick is skipped while the previous one is still
+    // out, so a slow backend never collects a pile of overlapping polls.
+    const pollInFlight = useRef(false);

-            if (statusRes.ok) setStatus(await statusRes.json());
-            if (metricsRes.ok) setMetrics(await metricsRes.json());
-            if (queueRes.ok) {
-                const queueData = await queueRes.json();
-                setQueue(queueData.items || []);
+    const fetchData = useCallback(async () => {
+        if (pollInFlight.current) return;
+        pollInFlight.current = true;
+
+        const load = async <T,>(url: string, apply: (data: T) => void) => {
+            const res = await fetch(url);
+            if (res.ok) apply(await res.json());
+        };
+
+        try {
+            const results = await Promise.allSettled([
+                load<ProcessingStatus>('/api/processing/status', setStatus),
+                load<Metrics>('/api/metrics', setMetrics),
+                load<{ items?: QueueItem[] }>('/api/processing/queue', (data) => setQueue(data.items || [])),
+                load<RedisStats>('/api/stats', setRedisStats),
+                load<{ failedFiles?: FailedFile[] }>('/api/processing/failed', (data) => setFailedFiles(data.failedFiles || [])),
+            ]);
+            for (const result of results) {
+                if (result.status === 'rejected') {
+                    console.error('Failed to fetch data:', result.reason);
+                }
            }
-            if (statsRes.ok) setRedisStats(await statsRes.json());
-            if (failedRes.ok) {
-                const failedData = await failedRes.json();
-                setFailedFiles(failedData.failedFiles || []);
-            }
-        } catch (err) {
-            console.error('Failed to fetch data:', err);
+        } finally {
+            pollInFlight.current = false;
        }
    }, []);

@@ -410,7 +416,7 @@ function Monitor() {
                    <h3 className="section-title">File Coverage</h3>
                    <div className="stats-grid">
                        <div className="stat-box">
-                            <div className="stat-value">{status?.uniqueHashes ? formatNumber(status.uniqueHashes) : (redisStats ? formatNumber(redisStats.fileCount) : '-')}</div>
+                            <div className="stat-value">{status?.uniqueHashes ? formatNumber(status.uniqueHashes) : (redisStats?.fileCount != null ? formatNumber(redisStats.fileCount) : '-')}</div>
                            <div className="stat-label">Unique Files</div>
                        </div>
                        <div className="stat-box">
@@ -432,7 +438,7 @@ function Monitor() {
                <div className="card total-size-card">
                    <h2>Total Size</h2>
                    <div className="total-size-value">
-                        {redisStats ? formatBytes(redisStats.totalSize) : '-'}
+                        {redisStats?.totalSize != null ? formatBytes(redisStats.totalSize) : '-'}
                    </div>
                    <div className="total-size-label">Watch Folders</div>
                </div>
@@ -184,12 +184,12 @@ export interface Metrics {

 // NOTE: DuplicateGroup and DuplicateData types have been moved to meta-dup service

+/** GET /api/stats: totals over meta-core's file-backed roots. */
 export interface RedisStats {
-    fileCount: number;
-    keyCount: number;
-    totalSize: number;
-    memoryUsage?: string;
-    memoryUsageBytes?: number;
+    /** null when meta-core cannot supply file totals (source 'unavailable') */
+    fileCount: number | null;
+    totalSize: number | null;
+    source?: 'meta-core' | 'unavailable';
 }

 export interface QueueItem {