# Background Tasks - `BackgroundTasks`

You can declare a parameter in a *path operation function* or dependency function with the type `BackgroundTasks`, and then you can use it to schedule the execution of background tasks after the response is sent.

You can import it directly from `fastapi`:

```python
from fastapi import BackgroundTasks
```

    private final AtomicInteger globalAttemptsInCurrentWindow = new AtomicInteger(0);
    private final AtomicLong currentWindowStart = new AtomicLong(System.currentTimeMillis());

    // Cleanup scheduler
    private final ScheduledExecutorService cleanupScheduler;
    private final AtomicBoolean closed = new AtomicBoolean(false);

    // Statistics
    private final AtomicLong totalAttemptsBlocked = new AtomicLong(0);

        public void scheduledTask(@CronExpression String schedule) {
            // Method for testing parameter annotation
        }
    }

    private static class TestConstructor {
        private final String schedule;

        public TestConstructor(@CronExpression String schedule) {
            this.schedule = schedule;
        }

        public String getSchedule() {

        .build();

    final long startNanos = System.nanoTime();
    final Call call = client.newCall(request);

    // Schedule a job to cancel the call in 1 second.
    executor.schedule(() -> {
      System.out.printf("%.2f Canceling call.%n", (System.nanoTime() - startNanos) / 1e9f);
      call.cancel();

    * Specifically the new controller watches the API server for scheduled pods. It processes each pod and ensures that any volumes that implement the volume Attacher interface are attached to the node their pod is scheduled to.

							<p><la:message key="labels.menu_crawl_config" /></p>
						</a>
					</li>
					</c:if>
					<c:if test="${fe:permission('admin-scheduler-view')}">
					<li class="nav-item">
						<a href="${fe:url('/admin/scheduler/')}" class="nav-link <c:if test="${param.menuType=='scheduler'}">active</c:if>">
							<em class='fa fa-genderless nav-icon'>
							<p><la:message key="labels.menu_scheduler_config" /></p>
						</a></li></c:if>

version: 2
updates:
  - package-ecosystem: "github-actions"
    directory: "/"
    schedule:
      interval: "daily"
    labels:
      - "@dev-productivity"
      - "a:chore"
      - "in:building-gradle"
  - package-ecosystem: "gradle"
    open-pull-requests-limit: 0
    directory: "/"
    schedule:
      interval: "daily"
    labels:
      - "@dev-productivity"
      - "a:chore"

            thresholdAdjustmentTask.cancel(false);
        }
        if (scheduler != null) {
            scheduler.shutdown();
        }
        log.info("[{}] Circuit breaker closed and resources cleaned up", name);
    }

    private void startDynamicThresholdAdjustment() {
        thresholdAdjustmentTask = scheduler.scheduleWithFixedDelay(this::performDynamicThresholdAdjustment, 30, 30, TimeUnit.SECONDS);

Pod Priority and Preemption in Kubernetes ([#564](https://github.com/kubernetes/enhancements/issues/564))

- Pod priority and preemption enables Kubernetes scheduler to schedule more important Pods first and when cluster is out of resources, it removes less important pods to create room for more important ones. The importance is specified by priority.

		<c:if test="${fe:permission('admin-scheduler')}">
			<li class="nav-item" data-toggle="tooltip" data-placement="left"
				title="<la:message key="labels.tooltip_run_crawler" />"><a class="nav-link"
									 href="${contextPath}/admin/scheduler/details/4/default_crawler"><em
					class="fa fa-play-circle"></a></li>
		</c:if>
		<c:if test="${not empty forumLink}">