Very high CPU consumption, Best approach for CPU usage

mediasoup libraries
13

FWIW, here’s how I calculate load. I don’t know if this is 100% correct, but it does appear to work.

The trick here, is that ru_stime and ru_utime are monotonically increasing, and are represented in milliseconds. Therefore, we just need to take slices of time, and compute the load over that slice of time.

async scheduleResourceUsage (timeout) {
    this.updateResourceUsage()
    this.timeout = setTimeout(() => this.scheduleResourceUsage(timeout), timeout)
  }

  async updateResourceUsage () {
    const { workerLoads, log } = this
    let updatedCPULoad = false
    for (const worker of this.workers) {
      const usage = await worker.getResourceUsage()
      const wall = Date.now()
      const { ru_stime: systemTime, ru_utime: userTime } = usage
      const total = systemTime + userTime
      const last = workerLoads.get(worker)
      let load
      let elapsed
      if (last) {
        const { wall: lastWall, total: lastTotal } = last
        elapsed = wall - lastWall
        const usage = total - lastTotal
        load = Number((usage / (elapsed * 1.0)).toFixed(3))
        updatedCPULoad = true
      }
      const result = { wall, systemTime, userTime, total, load, elapsed }
      log.silly(`Computed worker-${worker.pid} CPU usage`, result)
      workerLoads.set(worker, result)
    }
    if (updatedCPULoad) {
      return this.emit('updated-resource-usage')
    }
  }
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