Question

在简单的情况下，由于问题的性质，我将商店用作资源。

我有一些获取商店商品的请求。但是，某些获取请求具有更高的优先级，我希望它先得到处理。对于这种特殊的获取请求，我不希望遵循FIFO规则。

yield Store_item.get()

我尝试关注this question。但是，我无法创建适合此要求的子类。

我想要这样的东西：（但这是优先级资源的示例，而不是存储资源）。

def resource_user(name, env, resource, wait, prio):
    yield env.timeout(wait)
    with resource.request(priority=prio) as req:
         print('%s requesting at %s with priority=%s'% (name,env.now,prio))
         yield req
         print('%s got resource at %s' % (name, env.now))
         yield env.timeout(3)

但是，我需要它用于商店资源类，而不是商店的通用获取。

结果将是：

yield Store_item.priority_get()

Answer 1

我意识到我迟到了，但这对我有用。

首先，定义一个PriorityGet类（此代码改编自simpy的源代码）：

class PriorityGet(simpy.resources.base.Get):

    def __init__(self, resource, priority=10, preempt=True):
        self.priority = priority
        """The priority of this request. A smaller number means higher
        priority."""

        self.preempt = preempt
        """Indicates whether the request should preempt a resource user or not
        (:class:`PriorityResource` ignores this flag)."""

        self.time = resource._env.now
        """The time at which the request was made."""

        self.usage_since = None
        """The time at which the request succeeded."""

        self.key = (self.priority, self.time, not self.preempt)
        """Key for sorting events. Consists of the priority (lower value is
        more important), the time at which the request was made (earlier
        requests are more important) and finally the preemption flag (preempt
        requests are more important)."""

        super().__init__(resource)

然后，组装您的PriorityStore资源：

from simpy.core import BoundClass

class PriorityBaseStore(simpy.resources.store.Store):

    GetQueue = simpy.resources.resource.SortedQueue

    get = BoundClass(PriorityGet)

没有priority_get方法绑定到该类，但是您可以使用.get(priority = 1)（或任何其他小于10的数字，即PriorityGet中定义的基本优先级）获得相同的结果。类）。另外，您可以显式绑定该方法。

如何使优先级从资源存储获取请求

1 个答案: