擅长:python、mysql、java
<p>我最后用<a href="http://memcached.org/" rel="nofollow">memcached</a>来解决这个问题,因为它有原子更新。在</p>
<p>解决方案相当简单:</p>
<pre><code>import memcache
mc = memcache.Client(hosts, debug=1)
# to lock:
def request_lock(key, timeout=300):
if mc == None:
raise Exception("Memcache is not connected!")
# just store a "1" in that location - this is an atomic operation so if two
# nodes request a lock at the same time, only one of them will get a True
return mc.add(key, "1", timeout)
# to unlock:
def request_unlock(key):
if mc == None:
raise Exception("Memcache is not connected!")
return mc.delete(key) > 0
</code></pre>