Memory Copy Optimization for Streaming Gateway Transcoding：Models and Algorithms  

作　　者：LI Mingzhe WANG Jinlin CHEN Xiao YE Xiaozhou 

机构地区：[1]National Network New Media Engineering Research Center, Institute of Acoustics, Chinese Academy of Sciences, Beijing 100190, China [2]University of Chinese Academy of Sciences, Beijing 100190, China

出　　处：《Chinese Journal of Electronics》2016年第4期734-739,共6页电子学报（英文版）

基　　金：supported by the National Key Technology R&D Program(No.2012BAH02B01);the Key Deployment Project of Chinese Academy of Sciences(No.KGZD-EW-103-4)

摘　　要：Repeated memory copy during protocol translation inhibits capacity of a streaming media gateway.Unlike existing optimization techniques that rely on platform-specific features,this paper investigates algorithm-level platform-independent strategies.A mathematical concept of the buf-string is proposed to model the protocol transcoding process.Based on this model three payload extraction algorithms that can reduce memory copy are presented.The streaming gateway used in the Next-generation broadcasting(NGB) and the Nextgeneration on-demand(NGOD) system is taken as an example to demonstrate and evaluate our strategies.Experimental results from an x86 host and an embedded system prove that our strategies can reduce CPU overhead by 15%to 45%,and optimize the linear space complexity to a constant one.Repeated memory copy during protocol translation inhibits capacity of a streaming media gateway.Unlike existing optimization techniques that rely on platform-specific features,this paper investigates algorithm-level platform-independent strategies.A mathematical concept of the buf-string is proposed to model the protocol transcoding process.Based on this model three payload extraction algorithms that can reduce memory copy are presented.The streaming gateway used in the Next-generation broadcasting（NGB） and the Nextgeneration on-demand（NGOD） system is taken as an example to demonstrate and evaluate our strategies.Experimental results from an x86 host and an embedded system prove that our strategies can reduce CPU overhead by 15%to 45%,and optimize the linear space complexity to a constant one.

关 键 词：Streaming media Gateway Memory copy Automata Pattern matching 

分 类 号：TN919.8[电子电信—通信与信息系统] TP333[电子电信—信息与通信工程]