Efficiency of Cache Mechanism for Network Processors

With the explosion of network bandwidth and the ever-changing requirements for diverse network-based applications, the traditional processing architectures, i.e., general purpose processor (GPP) and application specific integrated circuits (ASIC) cannot provide sufficient flexibility and high performance at the same time. Thus, the network processor (NP) has emerged as an alternative to meet these dual demands for today's network processing. The NP combines embedded multi-threaded cores with a rich memory hierarchy that can adapt to different networking circumstances when customized by the application developers. In today's NP architectures, multithreading prevails over cache mechanism, which has achieved great success in GPP to hide memory access latencies. This paper focuses on the efficiency of the cache mechanism in an NP. Theoretical timing models of packet processing are established for evaluating cache efficiency and experiments are performed based on real-life network backbone traces. Testing results show that an improvement of nearly 70% can be gained in throughput with assistance from the cache mechanism. Accordingly, the cache mechanism is still efficient and irreplaceable in network processing, despite the existing of multithreading.     

茶叶的几种贮藏方法

贮藏茶叶要保持茶叶固有的色、香、味、形，因此必须设法充分保持干燥，尽量减少外界温度、湿度的影响，避免与带有异味的物品接触，还要使茶叶不受挤压和撞击，以保持其原形、本色、真味。下面介绍几种常见的茶叶贮藏方法：