v3.0.2

changelog.md

@@ -1,5 +1,28 @@
 # Changelog
 
+## 2026-03-02 - 3.0.2 - fix(pidusage)
+prune history entries for PIDs not present in the requested set to avoid stale data and memory growth
+
+- Deletes entries from the history map when a PID is not included in the current pids array
+- Prevents accumulation of stale PID histories and potential memory growth
+- Change implemented in ts/smartmetrics.pidusage.ts alongside the metrics result construction
+
+## 2026-02-19 - 3.0.1 - fix(smartmetrics)
+no code changes detected; no version bump or release required
+
+- git diff contained no modifications
+- current package.json version is 3.0.0
+- no dependency or file changes to warrant a release
+
+## 2026-02-19 - 3.0.0 - BREAKING CHANGE(smartmetrics)
+add system-wide metrics collection, Prometheus gauges, and normalized CPU reporting
+
+- Add new sysusage plugin (ts/smartmetrics.sysusage.ts) that reads /proc/stat and /proc/meminfo (with os fallback) and returns system CPU, memory and load averages.
+- Expose system-wide Prometheus gauges: smartmetrics_system_cpu_percent, smartmetrics_system_memory_used_percent, smartmetrics_system_memory_used_bytes, smartmetrics_system_load_avg_1, smartmetrics_system_load_avg_5, smartmetrics_system_load_avg_15.
+- Extend IMetricsSnapshot with system fields: systemCpuPercent, systemMemTotalBytes, systemMemAvailableBytes, systemMemUsedBytes, systemMemUsedPercent, systemLoadAvg1, systemLoadAvg5, systemLoadAvg15 (this is a breaking TypeScript API change).
+- Normalize per-process CPU in pidusage by adding cpuCoreCount and cpuNormalizedPercent and use cpuNormalizedPercent when aggregating CPU across the process tree.
+- Export the new sysusage plugin from ts/smartmetrics.plugins.ts and wire system metrics into metric collection and Prometheus gauge updates.
+
 ## 2026-02-19 - 2.0.11 - fix(deps)
 bump dependencies, update build script, expand README and npm metadata
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@push.rocks/smartmetrics",
-  "version": "2.0.11",
+  "version": "3.0.2",
   "private": false,
   "description": "A package for easy collection and reporting of system and process metrics.",
   "main": "dist_ts/index.js",
@@ -36,11 +36,7 @@
   ],
   "dependencies": {
     "@push.rocks/smartdelay": "^3.0.5",
-    "@push.rocks/smartlog": "^3.1.11",
-    "@types/pidusage": "^2.0.2",
-    "pidtree": "^0.6.0",
-    "pidusage": "^4.0.1",
-    "prom-client": "^15.1.3"
+    "@push.rocks/smartlog": "^3.1.11"
   },
   "type": "module",
   "keywords": [

pnpm-lock.yaml

@@ -14,18 +14,6 @@ importers:
       '@push.rocks/smartlog':
         specifier: ^3.1.11
         version: 3.1.11
-      '@types/pidusage':
-        specifier: ^2.0.2
-        version: 2.0.5
-      pidtree:
-        specifier: ^0.6.0
-        version: 0.6.0
-      pidusage:
-        specifier: ^4.0.1
-        version: 4.0.1
-      prom-client:
-        specifier: ^15.1.3
-        version: 15.1.3
     devDependencies:
       '@git.zone/tsbuild':
         specifier: ^4.1.2
@@ -693,10 +681,6 @@ packages:
   '@napi-rs/wasm-runtime@1.1.1':
     resolution: {integrity: sha512-p64ah1M1ld8xjWv3qbvFwHiFVWrq1yFvV4f7w+mzaqiR4IlSgkqhcRdHwsGgomwzBH51sRY4NEowLxnaBjcW/A==}
 
-  '@opentelemetry/api@1.9.0':
-    resolution: {integrity: sha512-3giAOQvZiH5F9bMlMiv8+GSPMeqg0dbaeo58/0SlA9sxSqZhnUtxzX9/2FzyhS9sWQf5S0GJE0AKBrFqjpeYcg==}
-    engines: {node: '>=8.0.0'}
-
   '@oxc-project/types@0.99.0':
     resolution: {integrity: sha512-LLDEhXB7g1m5J+woRSgfKsFPS3LhR9xRhTeIoEBm5WrkwMxn6eZ0Ld0c0K5eHB57ChZX6I3uSmmLjZ8pcjlRcw==}
 
@@ -1871,9 +1855,6 @@ packages:
   '@types/node@25.3.0':
     resolution: {integrity: sha512-4K3bqJpXpqfg2XKGK9bpDTc6xO/xoUP/RBWS7AtRMug6zZFaRekiLzjVtAoZMquxoAbzBvy5nxQ7veS5eYzf8A==}
 
-  '@types/pidusage@2.0.5':
-    resolution: {integrity: sha512-MIiyZI4/MK9UGUXWt0jJcCZhVw7YdhBuTOuqP/BjuLDLZ2PmmViMIQgZiWxtaMicQfAz/kMrZ5T7PKxFSkTeUA==}
-
   '@types/ping@0.4.4':
     resolution: {integrity: sha512-ifvo6w2f5eJYlXm+HiVx67iJe8WZp87sfa683nlqED5Vnt9Z93onkokNoWqOG21EaE8fMxyKPobE+mkPEyxsdw==}
 
@@ -2077,9 +2058,6 @@ packages:
     resolution: {integrity: sha512-4Bcg1P8xhUuqcii/S0Z9wiHIrQVPMermM1any+MX5GeGD7faD3/msQUDGLol9wOcz4/jbg/WJnGqoJF6LiBdtg==}
     engines: {node: '>=10.0.0'}
 
-  bintrees@1.0.2:
-    resolution: {integrity: sha1-SfiW1uhYpKSZ34XDj7OZua/4QPg=}
-
   body-parser@1.20.3:
     resolution: {integrity: sha512-7rAxByjUMqQ3/bHJy7D6OGXvx/MMc4IqBn/X0fcM1QUcAItpZrBEYhWGem+tzXH90c+G01ypMcYJBO9Y30203g==}
     engines: {node: '>= 0.8', npm: 1.2.8000 || >= 1.4.16}
@@ -3519,15 +3497,6 @@ packages:
     resolution: {integrity: sha512-5gTmgEY/sqK6gFXLIsQNH19lWb4ebPDLA4SdLP7dsWkIXHWlG66oPuVvXSGFPppYZz8ZDZq0dYYrbHfBCVUb1Q==}
     engines: {node: '>=12'}
 
-  pidtree@0.6.0:
-    resolution: {integrity: sha512-eG2dWTVw5bzqGRztnHExczNxt5VGsE6OwTeCG3fdUf9KBsZzO3R5OIIIzWR+iZA0NtZ+RDVdaoE2dK1cn6jH4g==}
-    engines: {node: '>=0.10'}
-    hasBin: true
-
-  pidusage@4.0.1:
-    resolution: {integrity: sha512-yCH2dtLHfEBnzlHUJymR/Z1nN2ePG3m392Mv8TFlTP1B0xkpMQNHAnfkY0n2tAi6ceKO6YWhxYfZ96V4vVkh/g==}
-    engines: {node: '>=18'}
-
   ping@0.4.4:
     resolution: {integrity: sha512-56ZMC0j7SCsMMLdOoUg12VZCfj/+ZO+yfOSjaNCRrmZZr6GLbN2X/Ui56T15dI8NhiHckaw5X2pvyfAomanwqQ==}
     engines: {node: '>=4.0.0'}
@@ -3552,10 +3521,6 @@ packages:
     resolution: {integrity: sha512-7PiHtLll5LdnKIMw100I+8xJXR5gW2QwWYkT6iJva0bXitZKa/XMrSbdmg3r2Xnaidz9Qumd0VPaMrZlF9V9sA==}
     engines: {node: '>=0.4.0'}
 
-  prom-client@15.1.3:
-    resolution: {integrity: sha512-6ZiOBfCywsD4k1BN9IX0uZhF+tJkV8q8llP64G5Hajs4JOeVLPCwpPVcpXy3BwYiUGgyJzsJJQeOIv7+hDSq8g==}
-    engines: {node: ^16 || ^18 || >=20}
-
   property-information@7.1.0:
     resolution: {integrity: sha512-TwEZ+X+yCJmYfL7TPUOcvBZ4QfoT5YenQiJuX//0th53DE6w0xxLEtfK3iyryQFddXuvkIk51EEgrJQ0WJkOmQ==}
 
@@ -3917,9 +3882,6 @@ packages:
   tar-stream@3.1.7:
     resolution: {integrity: sha512-qJj60CXt7IU1Ffyc3NJMjh6EkuCFej46zUqJ4J7pqYlThyd9bO0XBTmcOIhSzZJVWfsLks0+nle/j538YAW9RQ==}
 
-  tdigest@0.1.2:
-    resolution: {integrity: sha512-+G0LLgjjo9BZX2MfdvPfH+MKLCrxlXSYec5DaPYP1fe6Iyhf0/fSmJ0bFiZ1F8BT6cGXl2LpltQptzjXKWEkKA==}
-
   text-decoder@1.2.3:
     resolution: {integrity: sha512-3/o9z3X0X0fTupwsYvR03pJ/DjWuqqrfwBgTQzdWDiQSm9KitAyz/9WqsT2JQW7KV2m+bC2ol/zqpW37NHxLaA==}
 
@@ -5743,8 +5705,6 @@ snapshots:
       '@tybys/wasm-util': 0.10.1
     optional: true
 
-  '@opentelemetry/api@1.9.0': {}
-
   '@oxc-project/types@0.99.0': {}
 
   '@pdf-lib/standard-fonts@1.0.0':
@@ -7762,8 +7722,6 @@ snapshots:
     dependencies:
       undici-types: 7.18.2
 
-  '@types/pidusage@2.0.5': {}
-
   '@types/ping@0.4.4': {}
 
   '@types/qs@6.14.0': {}
@@ -7958,8 +7916,6 @@ snapshots:
 
   basic-ftp@5.0.5: {}
 
-  bintrees@1.0.2: {}
-
   body-parser@1.20.3:
     dependencies:
       bytes: 3.1.2
@@ -9663,12 +9619,6 @@ snapshots:
 
   picomatch@4.0.3: {}
 
-  pidtree@0.6.0: {}
-
-  pidusage@4.0.1:
-    dependencies:
-      safe-buffer: 5.2.1
-
   ping@0.4.4: {}
 
   pkg-dir@4.2.0:
@@ -9689,11 +9639,6 @@ snapshots:
 
   progress@2.0.3: {}
 
-  prom-client@15.1.3:
-    dependencies:
-      '@opentelemetry/api': 1.9.0
-      tdigest: 0.1.2
-
   property-information@7.1.0: {}
 
   proto-list@1.2.4: {}
@@ -10200,10 +10145,6 @@ snapshots:
       fast-fifo: 1.3.2
       streamx: 2.22.1
 
-  tdigest@0.1.2:
-    dependencies:
-      bintrees: 1.0.2
-
   text-decoder@1.2.3:
     dependencies:
       b4a: 1.6.7

readme.md

@@ -71,7 +71,7 @@ SmartMetrics doesn't just monitor your main process – it automatically discove
 The library automatically detects available memory whether running on bare metal, in Docker containers, or with Node.js heap restrictions. It picks the most restrictive of:
 
 1. **System total memory** (`os.totalmem()`)
-2. **Docker cgroup limit** (`/sys/fs/cgroup/memory/memory.limit_in_bytes`)
+2. **Docker cgroup limit** – supports both cgroup v2 (`/sys/fs/cgroup/memory.max`) and cgroup v1 (`/sys/fs/cgroup/memory/memory.limit_in_bytes`)
 3. **V8 heap size limit** (`v8.getHeapStatistics().heap_size_limit`)
 
 This ensures accurate percentage calculations regardless of environment.
@@ -101,8 +101,8 @@ Retrieves current system metrics as a structured object.
 ```typescript
 {
   process_cpu_seconds_total: number;    // Total CPU time in seconds
-  nodejs_active_handles_total: number;   // Active handles count
-  nodejs_active_requests_total: number;  // Active requests count
+  nodejs_active_handles_total: number;   // Always 0 (deprecated Node.js API; real values tracked by Prometheus default collectors)
+  nodejs_active_requests_total: number;  // Always 0 (deprecated Node.js API; real values tracked by Prometheus default collectors)
   nodejs_heap_size_total_bytes: number;  // V8 heap size in bytes
   cpuPercentage: number;                 // Aggregated CPU usage across all child processes
   cpuUsageText: string;                  // Human-readable CPU usage (e.g. "12.5 %")

test/test.ts

@@ -75,4 +75,4 @@ tap.test('should disable Prometheus endpoint', async () => {
   }
 });
 
-tap.start();
+export default tap.start();

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartmetrics',
-  version: '2.0.11',
+  version: '3.0.2',
   description: 'A package for easy collection and reporting of system and process metrics.'
 }

ts/smartmetrics.classes.smartmetrics.ts

@@ -5,41 +5,82 @@ export class SmartMetrics {
   public started = false;
   public sourceNameArg: string;
   public logger: plugins.smartlog.Smartlog;
-  public registry: plugins.promClient.Registry;
+  public registry: plugins.prom.Registry;
   public maxMemoryMB: number;
 
   // Prometheus gauges for custom metrics
-  private cpuPercentageGauge: plugins.promClient.Gauge<string>;
-  private memoryPercentageGauge: plugins.promClient.Gauge<string>;
-  private memoryUsageBytesGauge: plugins.promClient.Gauge<string>;
+  private cpuPercentageGauge: plugins.prom.Gauge;
+  private memoryPercentageGauge: plugins.prom.Gauge;
+  private memoryUsageBytesGauge: plugins.prom.Gauge;
+  private systemCpuPercentGauge: plugins.prom.Gauge;
+  private systemMemUsedPercentGauge: plugins.prom.Gauge;
+  private systemMemUsedBytesGauge: plugins.prom.Gauge;
+  private systemLoadAvg1Gauge: plugins.prom.Gauge;
+  private systemLoadAvg5Gauge: plugins.prom.Gauge;
+  private systemLoadAvg15Gauge: plugins.prom.Gauge;
 
   // HTTP server for Prometheus endpoint
   private prometheusServer?: plugins.http.Server;
   private prometheusPort?: number;
 
-  public async setup() {
-    const collectDefaultMetrics = plugins.promClient.collectDefaultMetrics;
-    this.registry = new plugins.promClient.Registry();
-    collectDefaultMetrics({ register: this.registry });
+  public setup() {
+    this.registry = new plugins.prom.Registry();
+    plugins.prom.collectDefaultMetrics(this.registry);
 
     // Initialize custom gauges
-    this.cpuPercentageGauge = new plugins.promClient.Gauge({
+    this.cpuPercentageGauge = new plugins.prom.Gauge({
       name: 'smartmetrics_cpu_percentage',
       help: 'Current CPU usage percentage',
       registers: [this.registry]
     });
 
-    this.memoryPercentageGauge = new plugins.promClient.Gauge({
+    this.memoryPercentageGauge = new plugins.prom.Gauge({
       name: 'smartmetrics_memory_percentage',
       help: 'Current memory usage percentage',
       registers: [this.registry]
     });
 
-    this.memoryUsageBytesGauge = new plugins.promClient.Gauge({
+    this.memoryUsageBytesGauge = new plugins.prom.Gauge({
       name: 'smartmetrics_memory_usage_bytes',
       help: 'Current memory usage in bytes',
       registers: [this.registry]
     });
+
+    this.systemCpuPercentGauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_cpu_percent',
+      help: 'System-wide CPU usage percentage',
+      registers: [this.registry]
+    });
+
+    this.systemMemUsedPercentGauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_memory_used_percent',
+      help: 'System-wide memory usage percentage',
+      registers: [this.registry]
+    });
+
+    this.systemMemUsedBytesGauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_memory_used_bytes',
+      help: 'System-wide memory used in bytes',
+      registers: [this.registry]
+    });
+
+    this.systemLoadAvg1Gauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_load_avg_1',
+      help: 'System 1-minute load average',
+      registers: [this.registry]
+    });
+
+    this.systemLoadAvg5Gauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_load_avg_5',
+      help: 'System 5-minute load average',
+      registers: [this.registry]
+    });
+
+    this.systemLoadAvg15Gauge = new plugins.prom.Gauge({
+      name: 'smartmetrics_system_load_avg_15',
+      help: 'System 15-minute load average',
+      registers: [this.registry]
+    });
   }
 
   constructor(loggerArg: plugins.smartlog.Smartlog, sourceNameArg: string) {
@@ -50,28 +91,32 @@ export class SmartMetrics {
   }
 
   private checkMemoryLimits() {
-    let heapStats = plugins.v8.getHeapStatistics();
-    let maxHeapSizeMB = heapStats.heap_size_limit / 1024 / 1024;
-    let totalSystemMemoryMB = plugins.os.totalmem() / 1024 / 1024;
+    const heapStats = plugins.v8.getHeapStatistics();
+    const maxHeapSizeMB = heapStats.heap_size_limit / 1024 / 1024;
+    const totalSystemMemoryMB = plugins.os.totalmem() / 1024 / 1024;
 
     let dockerMemoryLimitMB = totalSystemMemoryMB;
+
+    // Try cgroup v2 first, then fall back to cgroup v1
     try {
-      let dockerMemoryLimitBytes = plugins.fs.readFileSync(
+      const cgroupV2 = plugins.fs.readFileSync('/sys/fs/cgroup/memory.max', 'utf8').trim();
+      if (cgroupV2 !== 'max') {
+        dockerMemoryLimitMB = parseInt(cgroupV2, 10) / 1024 / 1024;
+      }
+    } catch {
+      try {
+        const cgroupV1 = plugins.fs.readFileSync(
           '/sys/fs/cgroup/memory/memory.limit_in_bytes',
           'utf8'
-      );
-      dockerMemoryLimitMB = parseInt(dockerMemoryLimitBytes, 10) / 1024 / 1024;
-    } catch (error) {
-      // Ignore - this will fail if not running in a Docker container
+        ).trim();
+        dockerMemoryLimitMB = parseInt(cgroupV1, 10) / 1024 / 1024;
+      } catch {
+        // Not running in a container — use system memory
+      }
     }
 
-    // Set the maximum memory to the lower value between the Docker limit and the total system memory
+    // Pick the most restrictive limit
     this.maxMemoryMB = Math.min(totalSystemMemoryMB, dockerMemoryLimitMB, maxHeapSizeMB);
-
-    // If the maximum old space size limit is greater than the maximum available memory, throw an error
-    if (maxHeapSizeMB > this.maxMemoryMB) {
-      throw new Error('Node.js process can use more memory than is available');
-    }
   }
 
   public start() {
@@ -104,20 +149,26 @@ export class SmartMetrics {
   }
 
   public async getMetrics() {
-    const pids = await plugins.pidtree(process.pid);
-    const stats = await plugins.pidusage([process.pid, ...pids]);
+    let pids: number[] = [];
+    try {
+      pids = await plugins.pidtree.getChildPids(process.pid);
+    } catch {
+      // pidtree can fail if process tree cannot be read
+    }
+    const stats = await plugins.pidusage.getPidUsage([process.pid, ...pids]);
 
+    // Aggregate normalized CPU (0-100% of total machine) across process tree
     let cpuPercentage = 0;
-    for (const stat of Object.keys(stats)) {
-      if (!stats[stat]) continue;
-      cpuPercentage += stats[stat].cpu;
+    for (const stat of Object.values(stats)) {
+      if (!stat) continue;
+      cpuPercentage += stat.cpuNormalizedPercent;
     }
     let cpuUsageText = `${Math.round(cpuPercentage * 100) / 100} %`;
 
     let memoryUsageBytes = 0;
-    for (const stat of Object.keys(stats)) {
-      if (!stats[stat]) continue;
-      memoryUsageBytes += stats[stat].memory;
+    for (const stat of Object.values(stats)) {
+      if (!stat) continue;
+      memoryUsageBytes += stat.memory;
     }
 
     let memoryPercentage =
@@ -126,7 +177,8 @@ export class SmartMetrics {
       memoryUsageBytes
     )} / ${this.formatBytes(this.maxMemoryMB * 1024 * 1024)}`;
 
-    console.log(`${cpuUsageText} ||| ${memoryUsageText} `);
+    // Get system-wide metrics
+    const systemUsage = await plugins.sysusage.getSystemUsage();
 
     // Update Prometheus gauges with current values
     if (this.cpuPercentageGauge) {
@@ -138,16 +190,32 @@ export class SmartMetrics {
     if (this.memoryUsageBytesGauge) {
       this.memoryUsageBytesGauge.set(memoryUsageBytes);
     }
+    if (this.systemCpuPercentGauge) {
+      this.systemCpuPercentGauge.set(systemUsage.cpuPercent);
+    }
+    if (this.systemMemUsedPercentGauge) {
+      this.systemMemUsedPercentGauge.set(systemUsage.memUsedPercent);
+    }
+    if (this.systemMemUsedBytesGauge) {
+      this.systemMemUsedBytesGauge.set(systemUsage.memUsedBytes);
+    }
+    if (this.systemLoadAvg1Gauge) {
+      this.systemLoadAvg1Gauge.set(systemUsage.loadAvg1);
+    }
+    if (this.systemLoadAvg5Gauge) {
+      this.systemLoadAvg5Gauge.set(systemUsage.loadAvg5);
+    }
+    if (this.systemLoadAvg15Gauge) {
+      this.systemLoadAvg15Gauge.set(systemUsage.loadAvg15);
+    }
 
     // Calculate Node.js metrics directly
     const cpuUsage = process.cpuUsage();
-    const process_cpu_seconds_total = (cpuUsage.user + cpuUsage.system) / 1000000; // Convert from microseconds to seconds
+    const process_cpu_seconds_total = (cpuUsage.user + cpuUsage.system) / 1000000;
 
     const heapStats = plugins.v8.getHeapStatistics();
     const nodejs_heap_size_total_bytes = heapStats.total_heap_size;
 
-    // Note: Active handles and requests are internal Node.js metrics that require deprecated APIs
-    // We return 0 here, but the Prometheus default collectors will track the real values
     const nodejs_active_handles_total = 0;
     const nodejs_active_requests_total = 0;
 
@@ -161,6 +229,14 @@ export class SmartMetrics {
       memoryPercentage,
       memoryUsageBytes,
       memoryUsageText,
+      systemCpuPercent: systemUsage.cpuPercent,
+      systemMemTotalBytes: systemUsage.memTotalBytes,
+      systemMemAvailableBytes: systemUsage.memAvailableBytes,
+      systemMemUsedBytes: systemUsage.memUsedBytes,
+      systemMemUsedPercent: systemUsage.memUsedPercent,
+      systemLoadAvg1: systemUsage.loadAvg1,
+      systemLoadAvg5: systemUsage.loadAvg5,
+      systemLoadAvg15: systemUsage.loadAvg15,
     };
     return returnMetrics;
   }

ts/smartmetrics.interfaces.ts

@@ -1,11 +1,21 @@
 export interface IMetricsSnapshot {
+  // existing process/node fields
   process_cpu_seconds_total: number;
   nodejs_active_handles_total: number;
   nodejs_active_requests_total: number;
   nodejs_heap_size_total_bytes: number;
-  cpuPercentage: number;
+  cpuPercentage: number;         // normalized to 0-100% of total machine
   cpuUsageText: string;
   memoryPercentage: number;
   memoryUsageBytes: number;
   memoryUsageText: string;
+  // system-wide fields
+  systemCpuPercent: number;
+  systemMemTotalBytes: number;
+  systemMemAvailableBytes: number;
+  systemMemUsedBytes: number;
+  systemMemUsedPercent: number;
+  systemLoadAvg1: number;
+  systemLoadAvg5: number;
+  systemLoadAvg15: number;
 }

ts/smartmetrics.pidtree.ts

@@ -0,0 +1,55 @@
+import * as fs from 'fs';
+
+// Get all descendant PIDs of the given root PID by reading /proc/<pid>/stat.
+// Returns an array of descendant PIDs (excludes the root itself).
+export async function getChildPids(rootPid: number): Promise<number[]> {
+  const parentMap = new Map<number, number[]>(); // parent → children
+
+  let entries: string[];
+  try {
+    entries = fs.readdirSync('/proc');
+  } catch {
+    return [];
+  }
+
+  for (const entry of entries) {
+    const pid = parseInt(entry, 10);
+    if (isNaN(pid)) continue;
+
+    try {
+      const stat = fs.readFileSync(`/proc/${pid}/stat`, 'utf8');
+      // Format: pid (comm) state ppid ...
+      // comm can contain spaces and parentheses, so find the last ')' first
+      const closeParenIdx = stat.lastIndexOf(')');
+      if (closeParenIdx === -1) continue;
+      const afterComm = stat.slice(closeParenIdx + 2); // skip ') '
+      const fields = afterComm.split(' ');
+      const ppid = parseInt(fields[1], 10); // field index 1 after state is ppid
+
+      if (!parentMap.has(ppid)) {
+        parentMap.set(ppid, []);
+      }
+      parentMap.get(ppid)!.push(pid);
+    } catch {
+      // Process may have exited between readdir and readFile
+      continue;
+    }
+  }
+
+  // BFS from rootPid to collect all descendants
+  const result: number[] = [];
+  const queue: number[] = [rootPid];
+
+  while (queue.length > 0) {
+    const current = queue.shift()!;
+    const children = parentMap.get(current);
+    if (children) {
+      for (const child of children) {
+        result.push(child);
+        queue.push(child);
+      }
+    }
+  }
+
+  return result;
+}

ts/smartmetrics.pidusage.ts

@@ -0,0 +1,136 @@
+import * as fs from 'fs';
+import * as os from 'os';
+import { execSync } from 'child_process';
+
+// CPU core count (cached at module load)
+const cpuCoreCount = typeof os.availableParallelism === 'function'
+  ? os.availableParallelism()
+  : os.cpus().length;
+
+// Cached system constants
+let clkTck: number | null = null;
+let pageSize: number | null = null;
+
+function getClkTck(): number {
+  if (clkTck === null) {
+    try {
+      clkTck = parseInt(execSync('getconf CLK_TCK', { encoding: 'utf8' }).trim(), 10);
+    } catch {
+      clkTck = 100; // standard Linux default
+    }
+  }
+  return clkTck;
+}
+
+function getPageSize(): number {
+  if (pageSize === null) {
+    try {
+      pageSize = parseInt(execSync('getconf PAGESIZE', { encoding: 'utf8' }).trim(), 10);
+    } catch {
+      pageSize = 4096; // standard Linux default
+    }
+  }
+  return pageSize;
+}
+
+// History for CPU delta tracking
+interface ISnapshot {
+  utime: number;
+  stime: number;
+  timestamp: number; // hrtime in seconds
+}
+
+const history = new Map<number, ISnapshot>();
+
+function readProcStat(pid: number): { utime: number; stime: number; rss: number } | null {
+  try {
+    const stat = fs.readFileSync(`/proc/${pid}/stat`, 'utf8');
+    // Format: pid (comm) state ppid ... fields
+    // utime is field 14, stime is field 15, rss is field 24 (1-indexed)
+    const closeParenIdx = stat.lastIndexOf(')');
+    if (closeParenIdx === -1) return null;
+    const afterComm = stat.slice(closeParenIdx + 2);
+    const fields = afterComm.split(' ');
+    // fields[0] = state (field 3), so utime = fields[11] (field 14), stime = fields[12] (field 15), rss = fields[21] (field 24)
+    const utime = parseInt(fields[11], 10);
+    const stime = parseInt(fields[12], 10);
+    const rss = parseInt(fields[21], 10);
+    return { utime, stime, rss };
+  } catch {
+    return null;
+  }
+}
+
+function hrtimeSeconds(): number {
+  const [sec, nsec] = process.hrtime();
+  return sec + nsec / 1e9;
+}
+
+export interface IPidUsageResult {
+  cpu: number;                  // raw per-core CPU% (can exceed 100%)
+  cpuCoreCount: number;         // number of CPU cores on the machine
+  cpuNormalizedPercent: number;  // cpu / coreCount — 0-100% of total machine
+  memory: number;               // RSS in bytes
+}
+
+/**
+ * Get CPU percentage and memory usage for the given PIDs.
+ * CPU% is calculated as a delta between successive calls.
+ */
+export async function getPidUsage(
+  pids: number[]
+): Promise<Record<number, IPidUsageResult>> {
+  const tck = getClkTck();
+  const ps = getPageSize();
+  const result: Record<number, IPidUsageResult> = {};
+
+  for (const pid of pids) {
+    const stat = readProcStat(pid);
+    if (!stat) {
+      continue;
+    }
+
+    const now = hrtimeSeconds();
+    const totalTicks = stat.utime + stat.stime;
+    const memoryBytes = stat.rss * ps;
+
+    const prev = history.get(pid);
+    if (prev) {
+      const elapsedSeconds = now - prev.timestamp;
+      const ticksDelta = totalTicks - (prev.utime + prev.stime);
+      const cpuSeconds = ticksDelta / tck;
+      const cpuPercent = elapsedSeconds > 0 ? (cpuSeconds / elapsedSeconds) * 100 : 0;
+
+      result[pid] = {
+        cpu: cpuPercent,
+        cpuCoreCount,
+        cpuNormalizedPercent: cpuPercent / cpuCoreCount,
+        memory: memoryBytes,
+      };
+    } else {
+      // First call for this PID — no delta available, report 0% cpu
+      result[pid] = {
+        cpu: 0,
+        cpuCoreCount,
+        cpuNormalizedPercent: 0,
+        memory: memoryBytes,
+      };
+    }
+
+    // Update history
+    history.set(pid, {
+      utime: stat.utime,
+      stime: stat.stime,
+      timestamp: now,
+    });
+  }
+
+  // Prune history entries for PIDs no longer in the requested set
+  for (const histPid of history.keys()) {
+    if (!pids.includes(histPid)) {
+      history.delete(histPid);
+    }
+  }
+
+  return result;
+}

ts/smartmetrics.plugins.ts

@@ -12,9 +12,10 @@ import * as smartlog from '@push.rocks/smartlog';
 
 export { smartdelay, smartlog };
 
-// third party scope
-import pidusage from 'pidusage';
-import pidtree from 'pidtree';
-import * as promClient from 'prom-client';
+// own implementations (replacing pidtree, pidusage, prom-client)
+import * as pidtree from './smartmetrics.pidtree.js';
+import * as pidusage from './smartmetrics.pidusage.js';
+import * as prom from './smartmetrics.prom.js';
+import * as sysusage from './smartmetrics.sysusage.js';
 
-export { pidusage, pidtree, promClient };
+export { pidtree, pidusage, prom, sysusage };

ts/smartmetrics.prom.ts

@@ -0,0 +1,671 @@
+import * as v8 from 'v8';
+import * as fs from 'fs';
+import { PerformanceObserver, monitorEventLoopDelay } from 'perf_hooks';
+
+// ── Metric types ────────────────────────────────────────────────────────────
+
+export interface IGaugeConfig {
+  name: string;
+  help: string;
+  registers?: Registry[];
+  labelNames?: string[];
+  collect?: () => void | Promise<void>;
+}
+
+export interface ICounterConfig {
+  name: string;
+  help: string;
+  registers?: Registry[];
+  labelNames?: string[];
+  collect?: () => void | Promise<void>;
+}
+
+export interface IHistogramConfig {
+  name: string;
+  help: string;
+  registers?: Registry[];
+  labelNames?: string[];
+  buckets?: number[];
+  collect?: () => void | Promise<void>;
+}
+
+interface IMetric {
+  name: string;
+  help: string;
+  type: string;
+  collect?: () => void | Promise<void>;
+  getLines(): Promise<string[]>;
+}
+
+// ── Registry ────────────────────────────────────────────────────────────────
+
+export class Registry {
+  private metricsList: IMetric[] = [];
+
+  registerMetric(metric: IMetric): void {
+    this.metricsList.push(metric);
+  }
+
+  async metrics(): Promise<string> {
+    const lines: string[] = [];
+    for (const m of this.metricsList) {
+      if (m.collect) {
+        await m.collect();
+      }
+      lines.push(`# HELP ${m.name} ${m.help}`);
+      lines.push(`# TYPE ${m.name} ${m.type}`);
+      lines.push(...(await m.getLines()));
+    }
+    return lines.join('\n') + '\n';
+  }
+}
+
+// ── Gauge ───────────────────────────────────────────────────────────────────
+
+export class Gauge implements IMetric {
+  public name: string;
+  public help: string;
+  public type = 'gauge';
+  public collect?: () => void | Promise<void>;
+  private value = 0;
+  private labelledValues = new Map<string, number>();
+  constructor(config: IGaugeConfig) {
+    this.name = config.name;
+    this.help = config.help;
+    this.collect = config.collect;
+    if (config.registers) {
+      for (const r of config.registers) {
+        r.registerMetric(this);
+      }
+    }
+  }
+
+  set(labelsOrValue: Record<string, string> | number, value?: number): void {
+    if (typeof labelsOrValue === 'number') {
+      this.value = labelsOrValue;
+    } else {
+      const key = this.labelsToKey(labelsOrValue);
+      this.labelledValues.set(key, value!);
+    }
+  }
+
+  inc(labelsOrAmount?: Record<string, string> | number, amount?: number): void {
+    if (labelsOrAmount === undefined) {
+      this.value += 1;
+    } else if (typeof labelsOrAmount === 'number') {
+      this.value += labelsOrAmount;
+    } else {
+      const key = this.labelsToKey(labelsOrAmount);
+      const cur = this.labelledValues.get(key) || 0;
+      this.labelledValues.set(key, cur + (amount ?? 1));
+    }
+  }
+
+  async getLines(): Promise<string[]> {
+    const lines: string[] = [];
+    if (this.labelledValues.size > 0) {
+      for (const [key, val] of this.labelledValues) {
+        lines.push(`${this.name}{${key}} ${formatValue(val)}`);
+      }
+    } else {
+      lines.push(`${this.name} ${formatValue(this.value)}`);
+    }
+    return lines;
+  }
+
+  /** Reset all values */
+  reset(): void {
+    this.value = 0;
+    this.labelledValues.clear();
+  }
+
+  private labelsToKey(labels: Record<string, string>): string {
+    return Object.entries(labels)
+      .map(([k, v]) => `${k}="${v}"`)
+      .join(',');
+  }
+}
+
+// ── Counter ─────────────────────────────────────────────────────────────────
+
+export class Counter implements IMetric {
+  public name: string;
+  public help: string;
+  public type = 'counter';
+  public collect?: () => void | Promise<void>;
+  private value = 0;
+  private labelledValues = new Map<string, number>();
+
+  constructor(config: ICounterConfig) {
+    this.name = config.name;
+    this.help = config.help;
+    this.collect = config.collect;
+    if (config.registers) {
+      for (const r of config.registers) {
+        r.registerMetric(this);
+      }
+    }
+  }
+
+  inc(labelsOrAmount?: Record<string, string> | number, amount?: number): void {
+    if (labelsOrAmount === undefined) {
+      this.value += 1;
+    } else if (typeof labelsOrAmount === 'number') {
+      this.value += labelsOrAmount;
+    } else {
+      const key = this.labelsToKey(labelsOrAmount);
+      const cur = this.labelledValues.get(key) || 0;
+      this.labelledValues.set(key, cur + (amount ?? 1));
+    }
+  }
+
+  async getLines(): Promise<string[]> {
+    const lines: string[] = [];
+    if (this.labelledValues.size > 0) {
+      for (const [key, val] of this.labelledValues) {
+        lines.push(`${this.name}{${key}} ${formatValue(val)}`);
+      }
+    } else {
+      lines.push(`${this.name} ${formatValue(this.value)}`);
+    }
+    return lines;
+  }
+
+  reset(): void {
+    this.value = 0;
+    this.labelledValues.clear();
+  }
+
+  private labelsToKey(labels: Record<string, string>): string {
+    return Object.entries(labels)
+      .map(([k, v]) => `${k}="${v}"`)
+      .join(',');
+  }
+}
+
+// ── Histogram ───────────────────────────────────────────────────────────────
+
+export class Histogram implements IMetric {
+  public name: string;
+  public help: string;
+  public type = 'histogram';
+  public collect?: () => void | Promise<void>;
+  private bucketBounds: number[];
+  private bucketCounts: number[];
+  private sum = 0;
+  private count = 0;
+  private labelledData = new Map<
+    string,
+    { bucketCounts: number[]; sum: number; count: number }
+  >();
+
+  constructor(config: IHistogramConfig) {
+    this.name = config.name;
+    this.help = config.help;
+    this.bucketBounds = config.buckets || [0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2.5, 5, 10];
+    this.bucketCounts = new Array(this.bucketBounds.length).fill(0);
+    this.collect = config.collect;
+    if (config.registers) {
+      for (const r of config.registers) {
+        r.registerMetric(this);
+      }
+    }
+  }
+
+  observe(labelsOrValue: Record<string, string> | number, value?: number): void {
+    if (typeof labelsOrValue === 'number') {
+      this.observeUnlabelled(labelsOrValue);
+    } else {
+      const key = this.labelsToKey(labelsOrValue);
+      let data = this.labelledData.get(key);
+      if (!data) {
+        data = {
+          bucketCounts: new Array(this.bucketBounds.length).fill(0),
+          sum: 0,
+          count: 0,
+        };
+        this.labelledData.set(key, data);
+      }
+      data.sum += value!;
+      data.count += 1;
+      for (let i = 0; i < this.bucketBounds.length; i++) {
+        if (value! <= this.bucketBounds[i]) {
+          data.bucketCounts[i]++;
+        }
+      }
+    }
+  }
+
+  private observeUnlabelled(val: number): void {
+    this.sum += val;
+    this.count += 1;
+    for (let i = 0; i < this.bucketBounds.length; i++) {
+      if (val <= this.bucketBounds[i]) {
+        this.bucketCounts[i]++;
+      }
+    }
+  }
+
+  async getLines(): Promise<string[]> {
+    const lines: string[] = [];
+    if (this.labelledData.size > 0) {
+      for (const [key, data] of this.labelledData) {
+        for (let i = 0; i < this.bucketBounds.length; i++) {
+          lines.push(
+            `${this.name}_bucket{${key},le="${this.bucketBounds[i]}"} ${data.bucketCounts[i]}`
+          );
+        }
+        lines.push(`${this.name}_bucket{${key},le="+Inf"} ${data.count}`);
+        lines.push(`${this.name}_sum{${key}} ${formatValue(data.sum)}`);
+        lines.push(`${this.name}_count{${key}} ${data.count}`);
+      }
+    } else {
+      for (let i = 0; i < this.bucketBounds.length; i++) {
+        lines.push(
+          `${this.name}_bucket{le="${this.bucketBounds[i]}"} ${this.bucketCounts[i]}`
+        );
+      }
+      lines.push(`${this.name}_bucket{le="+Inf"} ${this.count}`);
+      lines.push(`${this.name}_sum ${formatValue(this.sum)}`);
+      lines.push(`${this.name}_count ${this.count}`);
+    }
+    return lines;
+  }
+
+  reset(): void {
+    this.sum = 0;
+    this.count = 0;
+    this.bucketCounts.fill(0);
+    this.labelledData.clear();
+  }
+
+  private labelsToKey(labels: Record<string, string>): string {
+    return Object.entries(labels)
+      .map(([k, v]) => `${k}="${v}"`)
+      .join(',');
+  }
+}
+
+// ── Default Metrics Collectors ──────────────────────────────────────────────
+
+export function collectDefaultMetrics(registry: Registry): void {
+  registerProcessCpuTotal(registry);
+  registerProcessStartTime(registry);
+  registerProcessMemory(registry);
+  registerProcessOpenFds(registry);
+  registerProcessMaxFds(registry);
+  registerEventLoopLag(registry);
+  registerProcessHandles(registry);
+  registerProcessRequests(registry);
+  registerProcessResources(registry);
+  registerHeapSizeAndUsed(registry);
+  registerHeapSpaces(registry);
+  registerVersion(registry);
+  registerGc(registry);
+}
+
+function registerProcessCpuTotal(registry: Registry): void {
+  const userGauge = new Gauge({
+    name: 'process_cpu_user_seconds_total',
+    help: 'Total user CPU time spent in seconds.',
+    registers: [registry],
+    collect() {
+      const now = process.cpuUsage();
+      userGauge.set(now.user / 1e6);
+    },
+  });
+
+  const systemGauge = new Gauge({
+    name: 'process_cpu_system_seconds_total',
+    help: 'Total system CPU time spent in seconds.',
+    registers: [registry],
+    collect() {
+      const now = process.cpuUsage();
+      systemGauge.set(now.system / 1e6);
+    },
+  });
+
+  new Gauge({
+    name: 'process_cpu_seconds_total',
+    help: 'Total user and system CPU time spent in seconds.',
+    registers: [registry],
+    collect() {
+      const now = process.cpuUsage();
+      this.set((now.user + now.system) / 1e6);
+    },
+  });
+}
+
+function registerProcessStartTime(registry: Registry): void {
+  const startTimeSeconds = Math.floor(Date.now() / 1000 - process.uptime());
+  new Gauge({
+    name: 'process_start_time_seconds',
+    help: 'Start time of the process since unix epoch in seconds.',
+    registers: [registry],
+    collect() {
+      this.set(startTimeSeconds);
+    },
+  });
+}
+
+function registerProcessMemory(registry: Registry): void {
+  new Gauge({
+    name: 'process_resident_memory_bytes',
+    help: 'Resident memory size in bytes.',
+    registers: [registry],
+    collect() {
+      this.set(process.memoryUsage.rss());
+    },
+  });
+
+  new Gauge({
+    name: 'process_virtual_memory_bytes',
+    help: 'Virtual memory size in bytes.',
+    registers: [registry],
+    collect() {
+      try {
+        const status = fs.readFileSync('/proc/self/status', 'utf8');
+        const match = status.match(/VmSize:\s+(\d+)\s+kB/);
+        if (match) {
+          this.set(parseInt(match[1], 10) * 1024);
+        }
+      } catch {
+        // not on Linux — skip
+      }
+    },
+  });
+
+  new Gauge({
+    name: 'process_heap_bytes',
+    help: 'Process heap size in bytes.',
+    registers: [registry],
+    collect() {
+      this.set(process.memoryUsage().heapUsed);
+    },
+  });
+}
+
+function registerProcessOpenFds(registry: Registry): void {
+  new Gauge({
+    name: 'process_open_fds',
+    help: 'Number of open file descriptors.',
+    registers: [registry],
+    collect() {
+      try {
+        const fds = fs.readdirSync('/proc/self/fd');
+        this.set(fds.length);
+      } catch {
+        this.set(0);
+      }
+    },
+  });
+}
+
+function registerProcessMaxFds(registry: Registry): void {
+  new Gauge({
+    name: 'process_max_fds',
+    help: 'Maximum number of open file descriptors.',
+    registers: [registry],
+    collect() {
+      try {
+        const limits = fs.readFileSync('/proc/self/limits', 'utf8');
+        const match = limits.match(/Max open files\s+(\d+)/);
+        if (match) {
+          this.set(parseInt(match[1], 10));
+        }
+      } catch {
+        this.set(0);
+      }
+    },
+  });
+}
+
+function registerEventLoopLag(registry: Registry): void {
+  let histogram: ReturnType<typeof monitorEventLoopDelay> | null = null;
+  try {
+    histogram = monitorEventLoopDelay({ resolution: 10 });
+    histogram.enable();
+  } catch {
+    // Not available in this runtime
+  }
+
+  new Gauge({
+    name: 'nodejs_eventloop_lag_seconds',
+    help: 'Lag of event loop in seconds.',
+    registers: [registry],
+    collect() {
+      if (histogram) {
+        this.set(histogram.mean / 1e9);
+      }
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_eventloop_lag_min_seconds',
+    help: 'The minimum recorded event loop delay.',
+    registers: [registry],
+    collect() {
+      if (histogram) {
+        this.set(histogram.min / 1e9);
+      }
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_eventloop_lag_max_seconds',
+    help: 'The maximum recorded event loop delay.',
+    registers: [registry],
+    collect() {
+      if (histogram) {
+        this.set(histogram.max / 1e9);
+      }
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_eventloop_lag_mean_seconds',
+    help: 'The mean of the recorded event loop delays.',
+    registers: [registry],
+    collect() {
+      if (histogram) {
+        this.set(histogram.mean / 1e9);
+      }
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_eventloop_lag_stddev_seconds',
+    help: 'The standard deviation of the recorded event loop delays.',
+    registers: [registry],
+    collect() {
+      if (histogram) {
+        this.set(histogram.stddev / 1e9);
+      }
+    },
+  });
+
+  for (const p of [50, 90, 99]) {
+    new Gauge({
+      name: `nodejs_eventloop_lag_p${p}_seconds`,
+      help: `The ${p}th percentile of the recorded event loop delays.`,
+      registers: [registry],
+      collect() {
+        if (histogram) {
+          this.set(histogram.percentile(p) / 1e9);
+        }
+      },
+    });
+  }
+}
+
+function registerProcessHandles(registry: Registry): void {
+  new Gauge({
+    name: 'nodejs_active_handles_total',
+    help: 'Number of active libuv handles grouped by handle type.',
+    registers: [registry],
+    collect() {
+      const handles = (process as any)._getActiveHandles?.();
+      this.set(handles ? handles.length : 0);
+    },
+  });
+}
+
+function registerProcessRequests(registry: Registry): void {
+  new Gauge({
+    name: 'nodejs_active_requests_total',
+    help: 'Number of active libuv requests grouped by request type.',
+    registers: [registry],
+    collect() {
+      const requests = (process as any)._getActiveRequests?.();
+      this.set(requests ? requests.length : 0);
+    },
+  });
+}
+
+function registerProcessResources(registry: Registry): void {
+  new Gauge({
+    name: 'nodejs_active_resources_total',
+    help: 'Number of active resources that are currently keeping the event loop alive.',
+    registers: [registry],
+    collect() {
+      try {
+        const resources = (process as any).getActiveResourcesInfo?.();
+        this.set(resources ? resources.length : 0);
+      } catch {
+        this.set(0);
+      }
+    },
+  });
+}
+
+function registerHeapSizeAndUsed(registry: Registry): void {
+  new Gauge({
+    name: 'nodejs_heap_size_total_bytes',
+    help: 'Process heap size from Node.js in bytes.',
+    registers: [registry],
+    collect() {
+      this.set(process.memoryUsage().heapTotal);
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_heap_size_used_bytes',
+    help: 'Process heap size used from Node.js in bytes.',
+    registers: [registry],
+    collect() {
+      this.set(process.memoryUsage().heapUsed);
+    },
+  });
+
+  new Gauge({
+    name: 'nodejs_external_memory_bytes',
+    help: 'Node.js external memory size in bytes.',
+    registers: [registry],
+    collect() {
+      this.set(process.memoryUsage().external);
+    },
+  });
+}
+
+function registerHeapSpaces(registry: Registry): void {
+  const spaceGauge = new Gauge({
+    name: 'nodejs_heap_space_size_total_bytes',
+    help: 'Process heap space size total from Node.js in bytes.',
+    labelNames: ['space'],
+    registers: [registry],
+    collect() {
+      spaceGauge.reset();
+      const spaces = v8.getHeapSpaceStatistics();
+      for (const space of spaces) {
+        spaceGauge.set({ space: space.space_name }, space.space_size);
+      }
+    },
+  });
+
+  const usedGauge = new Gauge({
+    name: 'nodejs_heap_space_size_used_bytes',
+    help: 'Process heap space size used from Node.js in bytes.',
+    labelNames: ['space'],
+    registers: [registry],
+    collect() {
+      usedGauge.reset();
+      const spaces = v8.getHeapSpaceStatistics();
+      for (const space of spaces) {
+        usedGauge.set({ space: space.space_name }, space.space_used_size);
+      }
+    },
+  });
+
+  const availableGauge = new Gauge({
+    name: 'nodejs_heap_space_size_available_bytes',
+    help: 'Process heap space size available from Node.js in bytes.',
+    labelNames: ['space'],
+    registers: [registry],
+    collect() {
+      availableGauge.reset();
+      const spaces = v8.getHeapSpaceStatistics();
+      for (const space of spaces) {
+        availableGauge.set({ space: space.space_name }, space.space_available_size);
+      }
+    },
+  });
+}
+
+function registerVersion(registry: Registry): void {
+  const versionParts = process.version.slice(1).split('.').map(Number);
+  const gauge = new Gauge({
+    name: 'nodejs_version_info',
+    help: 'Node.js version info.',
+    labelNames: ['version', 'major', 'minor', 'patch'],
+    registers: [registry],
+    collect() {
+      gauge.set(
+        {
+          version: process.version,
+          major: String(versionParts[0]),
+          minor: String(versionParts[1]),
+          patch: String(versionParts[2]),
+        },
+        1
+      );
+    },
+  });
+}
+
+function registerGc(registry: Registry): void {
+  const gcHistogram = new Histogram({
+    name: 'nodejs_gc_duration_seconds',
+    help: 'Garbage collection duration by kind, in seconds.',
+    labelNames: ['kind'],
+    buckets: [0.001, 0.01, 0.1, 1, 2, 5],
+    registers: [registry],
+  });
+
+  const kindLabels: Record<number, string> = {
+    1: 'Scavenge',
+    2: 'Mark/Sweep/Compact',
+    4: 'IncrementalMarking',
+    8: 'ProcessWeakCallbacks',
+    15: 'All',
+  };
+
+  try {
+    const obs = new PerformanceObserver((list) => {
+      for (const entry of list.getEntries()) {
+        const gcEntry = entry as any;
+        const kind = kindLabels[gcEntry.detail?.kind ?? gcEntry.kind] || 'Unknown';
+        gcHistogram.observe({ kind }, entry.duration / 1000);
+      }
+    });
+    obs.observe({ entryTypes: ['gc'] });
+  } catch {
+    // GC observation not available
+  }
+}
+
+// ── Helpers ─────────────────────────────────────────────────────────────────
+
+function formatValue(v: number): string {
+  if (Number.isInteger(v)) return String(v);
+  return v.toString();
+}

ts/smartmetrics.sysusage.ts

@@ -0,0 +1,94 @@
+import * as fs from 'fs';
+import * as os from 'os';
+
+export interface ISystemUsageResult {
+  cpuPercent: number;          // 0-100% system-wide CPU utilization
+  memTotalBytes: number;       // total physical RAM
+  memAvailableBytes: number;   // available memory
+  memUsedBytes: number;        // memTotal - memAvailable
+  memUsedPercent: number;      // 0-100%
+  loadAvg1: number;            // 1-min load average
+  loadAvg5: number;            // 5-min load average
+  loadAvg15: number;           // 15-min load average
+}
+
+// History for system CPU delta tracking
+interface ICpuSnapshot {
+  idle: number;
+  total: number;
+}
+
+let prevCpuSnapshot: ICpuSnapshot | null = null;
+
+function readProcStat(): ICpuSnapshot | null {
+  try {
+    const content = fs.readFileSync('/proc/stat', 'utf8');
+    const firstLine = content.split('\n')[0]; // "cpu  user nice system idle iowait irq softirq steal ..."
+    const parts = firstLine.split(/\s+/).slice(1).map(Number);
+    // parts: [user, nice, system, idle, iowait, irq, softirq, steal, ...]
+    const idle = parts[3] + (parts[4] || 0); // idle + iowait
+    const total = parts.reduce((sum, v) => sum + v, 0);
+    return { idle, total };
+  } catch {
+    return null;
+  }
+}
+
+function getMemoryInfo(): { totalBytes: number; availableBytes: number } {
+  try {
+    const content = fs.readFileSync('/proc/meminfo', 'utf8');
+    let memTotal = 0;
+    let memAvailable = 0;
+    for (const line of content.split('\n')) {
+      if (line.startsWith('MemTotal:')) {
+        memTotal = parseInt(line.split(/\s+/)[1], 10) * 1024; // kB to bytes
+      } else if (line.startsWith('MemAvailable:')) {
+        memAvailable = parseInt(line.split(/\s+/)[1], 10) * 1024;
+      }
+    }
+    if (memTotal > 0 && memAvailable > 0) {
+      return { totalBytes: memTotal, availableBytes: memAvailable };
+    }
+  } catch {
+    // fall through to os fallback
+  }
+  // Fallback using os module
+  const totalBytes = os.totalmem();
+  const availableBytes = os.freemem();
+  return { totalBytes, availableBytes };
+}
+
+export async function getSystemUsage(): Promise<ISystemUsageResult> {
+  // CPU
+  let cpuPercent = 0;
+  const currentSnapshot = readProcStat();
+  if (currentSnapshot && prevCpuSnapshot) {
+    const totalDelta = currentSnapshot.total - prevCpuSnapshot.total;
+    const idleDelta = currentSnapshot.idle - prevCpuSnapshot.idle;
+    if (totalDelta > 0) {
+      cpuPercent = ((totalDelta - idleDelta) / totalDelta) * 100;
+    }
+  }
+  if (currentSnapshot) {
+    prevCpuSnapshot = currentSnapshot;
+  }
+
+  // Memory
+  const mem = getMemoryInfo();
+  const memUsedBytes = mem.totalBytes - mem.availableBytes;
+  const memUsedPercent = mem.totalBytes > 0 ? (memUsedBytes / mem.totalBytes) * 100 : 0;
+
+  // Load averages
+  const [loadAvg1, loadAvg5, loadAvg15] = os.loadavg();
+
+  return {
+    cpuPercent,
+    memTotalBytes: mem.totalBytes,
+    memAvailableBytes: mem.availableBytes,
+    memUsedBytes,
+    memUsedPercent,
+    loadAvg1,
+    loadAvg5,
+    loadAvg15,
+  };
+}