Moving Beyond Population-Centric vs. Enemy-Centric Counterinsurgency

Historically, insurgency is one of the most prevalent forms of armed conflict and it is likely to remain common in the foreseeable future. Recent experiences with counterinsurgency in Iraq and Afghanistan offer many lessons for future counterinsurgents, but the discourse on the subject continues to be mired in a traditional dichotomy pitting population-centric approaches to counterinsurgency against enemy-centric approaches. Historical analysis suggests that this traditional dichotomy is not a sufficiently nuanced way to understand or plan for such operations. Instead, discussions of counterinsurgency should focus on two dimensions: actions (use of physical force vs. political or moral actions) and targets (active insurgents vs. insurgent support). This perspective divides the space of possible counterinsurgency efforts into four quadrants, suggesting that effective counterinsurgency campaigns find a balance of effort across the four quadrants that is well matched to the specific context.     

Spaghetti: systems thinking and the US Army

In the mid-2000s, the United States Army was embroiled in counterinsurgency missions in Iraq and Afghanistan that required deeper understanding of local social systems. The Army turned to systems thinking and design thinking to model and understand the world, define problems, and develop approaches to strategic and operational challenges. However, the Army’s approach as expressed in publications and doctrine encourages the development of complicated, unsupported, and unfalsifiable hypotheses. The risk is that the Army will act on incorrect assumptions and develop plans that are fragile.     

Introduction: one-and-a-half cheers for the EU Global Strategy

EU High Representative Federica Mogherini presented her EU Global Strategy (EUGS) in June 2016. Encircled by security crises, it is difficult to think of something more important for Europe than collective action with the aim of weathering the storm. The EUGS, in this respect, seeks to define common ends and identify means. So what do we make of the EUGS? What does the EUGS tell us about the current role of the EU in global affairs? And how will the withdrawal of the UK from the EU affect foreign and security policy? As a way of introduction to the forum, this article notes that the EUGS focuses on the neighbourhood, puts the interests of European citizens first, identifies civilian means, and has created momentum on security policy. The key question, however, remains whether there is any interest in the EUGS beyond the foreign policy elites.     

面向大规模集群的并行I/O用户层配置优化策略

影响应用I/O性能的关键因素主要有三个层次:包括应用的I/O接口实现、体系结构和文件系统组件的性能以及应用的I/O参数配置。从应用I/O配置优化的视角,分析了大规模集群并行I/O的配置调优空间,在此基础上,给出了一套大规模集群并行I/O性能特征测试分析方法。基于该方法,在某国产超级计算集群上开展了一系列I/O测试分析来刻画系统的I/O性能特征,进而指导并行应用程序的I/O配置优化。基于优化后的配置参数,在两类典型的并行I/O场景中,针对某类生产应用程序,8192进程下的重启动数据写操作时间下降了15%,4096核的程序作业加载时间从10 min缩短到了5 s。     

面向大规模集群并行I/O的用户层配置优化策略研究

近年来，大规模并行场景下的I/O性能越来越受到应用科学家的关注。影响应用I/O性能的关键因素主要有三个层次：包括应用的I/O接口实现、体系结构和文件系统组件的性能以及应用的I/O参数配置。本文从应用I/O配置优化的视角，分析了大规模集群并行I/O的配置调优空间，在此基础上，给出了一套大规模集群并行I/O性能特征测试分析方法，基于该方法，在某国产超级计算集群上开展了一系列I/O测试分析来刻画系统的I/O性能特征，进而指导并行应用程序的I/O配置优化。基于优化后的配置参数，在两类典型的并行I/O场景中，针对某类生产应用程序，8192进程下的重启动数据写操作时间下降了15%，4096核的程序作业加载时间从10分钟缩短到了5s。本文提出的I/O配置调优空间及优化方法，可以推广应用到其它同类系统平台，对于大规模集群上的用户层并行I/O配置调优具有借鉴意义。