Function drainQueue

apps/sim/lib/execution/isolated-vm.ts:1265–1299

* Called after every completion or worker spawn — dispatches queued * executions to available workers.

()

 * executions to available workers.
 */
function drainQueue() {
  while (queueLength() > 0 && totalActiveExecutions < MAX_CONCURRENT) {
    const worker = selectWorker()
    if (!worker) {
      const activeWorkerCount = [...workers.values()].filter((w) => !w.retiring).length
      const currentPoolSize = activeWorkerCount + spawnInProgress
      if (currentPoolSize < POOL_SIZE) {
        spawnWorker()
          .then(() => drainQueue())
          .catch((err) => {
            logger.error('Failed to spawn worker during drain', { err })
            scheduleDrainRetry()
          })
      }
      break
    }

    const owner = selectOwnerForDispatch()
    if (!owner) {
      scheduleDrainRetry()
      break
    }

    const queued = shiftQueuedExecutionForOwner(owner)
    if (!queued) {
      owner.burstRemaining = 0
      maybeCleanupOwner(owner.ownerKey)
      continue
    }
    clearTimeout(queued.queueTimeout)
    // Clearing queueId: from here on, abort must reach the worker, not the queue.
    queued.state.queueId = undefined
    dispatchToWorker(worker, owner, queued.req, queued.resolve, queued.state, queued.brokers)
  }
}

/**
 * Execute JavaScript code in an isolated V8 isolate via Node.js subprocess.