memcached可以用于锁定吗？(Can memcached be used for locking?)

 memcached可用于缓存静态数据，减少数据库查找，通常用于memcached.get(id)和memcached.set(id) 。 
 
 但是将它用于锁定机制是否可以？ memcache.set和memcached.get是否总是提供数据（如果存在），或者如果请求花费太多时间它会返回None吗？ 
 
 我想避免并发访问由id标识的特定资源，我使用此逻辑： 
 
def access(id):
    if memcache.get(id):
        return access
    else:
        memcache.set(id)
        return true
 
 如果任何用户试图访问该资源，如果memcache.get(id) = username返回一个值，我们拒绝访问，否则我们执行memcache.set(id) = username以停止后续访问并允许当前用户访问。 
 
 这样使用memcached可以吗？ 将set并实际提供数据，如果它可用，无论花费多少时间，或者它在最短的时间内从我找到的任何内容中获得最佳结果（例如： 保证的memcached锁 ）到目前为止属于前一类和可能无法锁定以为它可能在99％的时间内起作用。 
 
 任何人都可以澄清，是否有其他锁定机制？ 

memcached can be used for a caching static data which reduces database lookup and typically does memcached.get(id) and memcached.set(id).
 
However is it fine to use this for locking mechanisms? Does memcache.set and memcached.get always give the data if it is present or will it just return None if the request is taking too much time?
 
I want to avoid concurrent access to a particular resource identified by a id and I use this logic:
 
def access(id):
    if memcache.get(id):
        return access
    else:
        memcache.set(id)
        return true
 
If any user tries to access that resource, if memcache.get(id) = username returns a value we decline the access else we do memcache.set(id) = username to stop subsequent access and allow access for the current user.
 
Is it fine to using memcached like this? Will set and get actually give the data if its available regardless of the time it takes or does it give best possible result in the least possible time from whatever I have found (for example: Guaranteed memcached lock) so far is of the former category and might not work for locking thought it might work 99% of the time.
 
Can anyone clarify and if there are alternative locking mechanisms?

原文：https://stackoverflow.com/questions/37458587