具有有限缓冲区的生产者/消费者，具有信号量的多个生产者/消费者
我有点陷入多重消费者/生产者问题。它出现在我的讲义中，但我根本无法理解为什么单一消费者/生产者方法行不通。
1 个消费者和 1 个生产者的典型方法如下所示：
Producer :
while(true)
emptyBuffers.P();
mutex.P();
buffer.insert(produced item);
mutex.V();
fullBuffers.V();
Consumer :
while(true)
fullBuffers.P();
mutex.P();
buffer.consume(consumed item);
mutex.V();
emptyBuffers.V();
如果我有超过 1 个生产者和/或超过 1 个消费者，为什么这不起作用？我到处都找过，但找不到我理解的答案：s。
互斥信号量确保没有 2 个进程同时在缓冲区中工作，因此我不知道如果您有更多进程，此属性可能会如何更改...
“解决方案”是将互斥锁更改为ProducerMutex 和 ConsumerMutex。但现在这意味着生产者和消费者可以同时在缓冲区中，这是不允许的，对吧？
我真的不明白：s
I'm a bit stuck on the multiple consumer/producer problem. It appears in my lecture notes, but I simply cannot understand why the single consumer/producer approach won't work.
The typical approach for 1 consumer and 1 producer looks like this :
Producer :
while(true)
emptyBuffers.P();
mutex.P();
buffer.insert(produced item);
mutex.V();
fullBuffers.V();
Consumer :
while(true)
fullBuffers.P();
mutex.P();
buffer.consume(consumed item);
mutex.V();
emptyBuffers.V();
Why will this not work if I have more than 1 producer and/or more than 1 consumer? I've looked everywhere, but I can't find an answer I understand :s.
The mutex semaphore makes sure there are no 2 processes working in the buffer at the same time, so I don't see how this property can possibly change if you have more processes...
The 'solution' is that you change the mutex into a ProducerMutex and a ConsumerMutex. But now that would mean a producer and a consumer CAN be in the buffer at the same time, which should not be allowed, right?
I'm really not getting this :s
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这是 http://en.wikipedia.org/wiki/Producer-consumer_problem（模命名）。当然，这也表明您不需要 1P/1C 版本的互斥体（如果缓冲区只有 1 个插槽，则这将是有效的）。但它也与 http://cs.gmu 中给出的解决方案相同。 edu/cne/modules/ipc/purple/prodsem.html。
底线：我认为你已经得到了这个很好，而无论是谁给你这个 2-mutex“解决方案”都不是。
That's the solution given in http://en.wikipedia.org/wiki/Producer-consumer_problem (modulo naming). Of course, that also states that you don't need the mutex for the 1P/1C version (which would be valid if the buffer had only 1 slot). But its also the same solution as given in http://cs.gmu.edu/cne/modules/ipc/purple/prodsem.html.
Bottom line: I think you're getting this just fine, and whomever gave you this 2-mutex "solution" isn't.