基于ARMLinux的EWS过载性能研究

在EWS(嵌入式Web服务器)过载情况下,网络包以泊松流的形式高速到达,MCU(微处理器)几乎被完全用于网卡中断处理,高层的处理任务得不到执行,EWS就出现了系统拥塞现象。在此情况下,对一个基于ARMLinux的EWS的收包过程进行了分析,并把EWS的收包过程抽象为网卡中断处理和TCP/IP处理两部分。根据二级串连排队网络的理论,建立了收包过程模型并对此模型进行了分析,提出了一种在轻量过载的情况下,使用轮询机制处理,在系统拥塞非常严重的情况下,触发关中断处理的轮询-关中断耦合的EWS拥塞解决方案。最后对一个基于ARMLinux的EWS的性能进行了试验分析和验证。

Research on performance analysis of overloaded EWS based on ARMLinux

When an EWS overloads, packets arrive with the high speed of passion speed. MCU is almost completely used to process NIC interruption. Thus, the high-level tasks cannot be executed absolutely, with a receiving livelock occuring in EWS. For such a case, an analysis was made for the receiving process of an EWS based on ARMLinux, and the receive-packet process had been viewed as two parts, ie., the NIC interrupting process and TCP/IP process. According to the theory of 2-level serial queuing network system, an improved method -polling and closing interrupt coupled method - was proposed by means of establishing a model of receive-packet process and analyzing in detail. When the light overwork occurs, the poll method was triggered. And when the overwork was heavy, the closing Interrupt method was used. The method had been analyzed and verified through testings with an EWS based on ARMLinux.