j.jmu.Lock()
	j.jobCancelers[req.ID] = jcancel
	j.jmu.Unlock()
	req.ctx = jctx

	select {
	case <-j.ctx.Done():
		j.once.Do(func() {
			xioutil.SafeClose(j.jobCh)
		})
	case j.jobCh <- req:
	default:
		return fmt.Errorf("batch job queue is currently full please try again later %#v", req)
	}
	return nil
}

// delete canceler from the map, cancel job if requested