写了一个长连接服务，但是在压测的时候发现，内存一直不回收。在消息发送完毕之后，CPU的使用率都W为0的情况，通过jhat来分析内存，发现临时变量都没有自动回收。
这应该如何定位呢？一般的思路是怎样的呢？
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