并行程序性能分析中的时戳同步技术  

Timestamp Synchronization in Parallel Application Performance Analysis

作　　者：杜祝平[1] 于磊[1] 李志博[1] 侯雪梅[2] 

机构地区：[1]信息工程大学信息工程学院,河南郑州450002 [2]信息工程大学理学院,河南郑州450001

出　　处：《信息工程大学学报》2011年第5期607-611,617,共6页Journal of Information Engineering University

基　　金：国家863计划资助项目(2009AA012201);上海市科委重大科技攻关项目(08dz501600)

摘　　要：在分析基于消息传递的并行应用程序性能时,常用的一种技术是事件跟踪。它要求事件记录的时戳要有可比较性。然而,集群计算机各处理器的时钟往往具有不同的时钟值和不同的漂移率。因此,在分析之前必须对采集的事件记录时戳进行同步。文章介绍了一种逻辑时戳同步方法,通过检测时钟条件违反情况,采用前向和后向分摊技术后移某些事件来修正逻辑错误的时戳,并根据集合通信操作的语义,将集合操作分解成类似于点到点通信的发送-接收对集合,从而将算法扩展到能够处理集合操作。最终,实现了事件的逻辑同步,并平滑了因后移事件而引起的事件不连续跳跃。Events tracking is a common technique in performance analysis of parallel applications based on message-passing.This technique requires that the timestamps of events be comparable.But the clocks of processors in a cluster system often have different time values and distinctive drift rates.So event timestamps have to be synchronized before analyzing those events.A logic timestamp synchronization technique is introduced,which corrects the timestamps that are wrong in logic by moving some events backwards or forwards.Based on the semantics of collective communication,collective operations are decomposed into sender-receiver pairs,which means this method can be expanded to handle collective operations.With this method,events can be synchonized in logic and events discontinuity can be smoothed.

关 键 词：性能分析 时戳同步 点到点通信 集合通信 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]