code: func (a *PanicOnExceed) Action(t *Tracker) {
  	a.mutex.Lock()
  	if a.acted {
  		a.mutex.Unlock()
  		return
  	}
  	a.acted = true
  	a.mutex.Unlock()
  	panic(PanicMemoryExceed + t.String())
  }
docs: // Action panics when memory usage exceeds memory quota.