高性能的消息框架 go-disruptor
这是Go编程语言里 LMAX Disruptor的接口。 它保留了Disruptor的本质和原理，并利用了很多相同的抽象概念和理论，但不会保持同样的API。
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简述：
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在我的 MacBook Pro (Intel Core i7-4960HQ CPU @ 2.60GHz) 中，我使用了 Go 1.4.2, 此版本使我能在一秒内发送9亿多份邮件(是的，你没有听错)， 从一个goroutine到另一个goroutine. 讯息在两台CPU间的传递很简单。 请注意，您的里程可能会有所不同，通过控制CPU并清除其缓存，不同的操作系统可以添加特定的“jitter”到App中。Linux和Windows系统有给定的进程分配给特定的CPU内核它通过将所有的CPU缓存热显著降低“jitter”的能力。 顺便，当Disruptor代码被编译并在Nexus 5上运行，它可以每秒可推送约15-20万条信息。
一旦被初始化，在运行时，Disruptor杰出设计的考虑因素之一，就是以一个恒定的速率来处理消息。为此，它使用两个主要技术：
1. 它避免了在所有costs上使用锁，costs通常会引起CPU内核间的排斥，影响可测量性。
2. 它允许应用程序预先在一个环形缓冲区分配连续的空间，不产生垃圾。
通过避免垃圾，垃圾清理站和应用程序暂停的功能可以免去。
**示例代码：**
Wireup ****
<pre class="brush:cpp ;toolbar: true; auto-links: false;">runtime.GOMAXPROCS(2) // make sure we have enough cores available to execute
const RingBufferCapacity = 1024 // must be a power of 2
const RingBufferMask = RingBufferCapacity - 1
// this instance will be shared among producers and consumers of this application
var ringBuffer = [RingBufferCapacity]MyStruct{}
myDisruptor := disruptor.
Configure(RingBufferCapacity).
WithConsumerGroup(MyConsumer{}). // we can have a set of concurrent consumers run first
// WithConsumerGroup(MyConsumer{}). // and then run this/these consumers after the first set of consumers
BuildShared() // Build() = single producer vs BuildShared() = multiple producers
myDisruptor.Start()
defer myDisruptor.Stop() // clean shutdown which stops all idling consumers after all published items have been consumed
// application code here, e.g. listen to HTTP, read from a network socket, etc.</pre>
生产者
<pre class="brush:cpp ;toolbar: true; auto-links: false;">Producer
writer := myDisruptor.Writer()
// for each item received from a network socket, e.g. UDP packets, HTTP request, etc. etc.
sequence := writer.Reserve(1) // reserve 1 slot on the ring buffer and give me the upper-most sequence of the reservation
// this could be written like this: ringBuffer[sequence%RingBufferCapacity] but the Mask and & operator is faster.
ringBuffer[sequence&RingBufferMask].MyImportStructData = ... // data from network stream
writer.Commit(sequence, sequence) // the item is ready to be consumed</pre>
消费者
<pre class="brush:cpp ;toolbar: true; auto-links: false;">type MyConsumer struct{}
func (m MyConsumer) Consume(lowerSequence, upperSequence int64) {
for sequence := lowerSequence; sequence <= upperSequence; sequence++ {
message := ringBuffer[sequence&RingBufferMask] // see performance note on producer sample above
// handle the incoming message with your application code
}
}</pre>
