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Scaling out NUMA-Aware Applications with RDMA-Based Distributed Shared Memory

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Journal of Computer Science & Technology 2019年第1期34卷 94-112页

作者： Yang Hong Yang Zheng Fan Yang Bin-Yu Zang hai-Bing Guan hai-bo chen Shanghai Key Laboratory for Scalable Computing Systems Shanghai Jiao Tong UniversityShanghai 200240China

The multicore evolution has stimulated renewed interests in scaling up applications on shared-memory multiprocessors,significantly improving the scalability of many *** the scalability is limited within a single node;therefore programmers still have to redesign applications to scale out over multiple *** paper revisits the design and implementation of distributed shared memory (DSM)as a way to scale out applications optimized for non-uniform memory access (NUMA)architecture over a well-connected *** paper presents MAGI,an efficient DSM system that provides a transparent shared address space with scalable performance on a cluster with fast network *** is unique in that it presents a NUMA abstraction to fully harness the multicore resources in each node through hierarchical synchronization and memory *** also exploits the memory access patterns of big-data applications and leverages a set of optimizations for remote direct memory access (RDMA)to reduce the number of page faults and the cost of the coherence *** has been implemented as a user-space library with pthread-compatible interfaces and can run existing multithreaded applications with minimized *** deployed MAGI over an 8-node RDMA-enabled *** evaluation shows that MAGI achieves up to 9.25:4 speedup compared with an unoptimized implementation,leading to a sealable performance for large-scale data-intensive applications.

关键词： distributed shared memory (DSM) scalability multieore evolution non-uniform memory access (NUMA) remote direct memory access (RDMA)

ShadowEth： Private Smart Contract on Public Blockchain

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Journal of Computer Science & Technology 2018年第3期33卷 542-556页

作者： Rui Yuan Yu-Bin Xia hai-bo chen Bin-Yu Zang Jan Xie Institute of Parallel and Distributed Systems Shanghai Jiao Tong University Shanghai 200240 China Cryptape Inc. Hangzhou 310007 China

Blockchain is becoming popular as a distributed and reliable ledger which allows distrustful parties to transact safely without trusting third parties. Emerging blockchain systems like Ethereum support smart contracts where miners can run arbitrary user-defined programs. However, one of the biggest concerns about the blockchain and the smart contract is privacy, since all the transactions on the chain are exposed to the public. In this paper, we present ShadowEth, a system that leverages hardware enclave to ensure the confidentiality of smart contracts while keeping the integrity and availability based on existing public blockchains like Ethereum. ShadowEth establishes a confidential and secure platform protected by trusted execution environment （TEE） off the public blockchain for the execution and storage of private contracts. It only puts the process of verification on the blockchain. We provide a design of our system including a protocol of the cryptographic communication and verification and show the applicability and feasibility of ShadowEth by various case studies. We implement a prototype using the Intel SGX on the Ethereum network and analyze the security and availability of the system.

关键词： blockchain smart contract privacy trusted execution environment hardware-enclave

Revisiting Persistent Indexing Structures on Intel Optane DCPersistent Memory

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Journal of Computer Science & Technology 2021年第1期36卷 140-157页

作者： Heng Bu Ming-Kai Dong Ji-Fei Yi Bin-Yu Zang hai-bo chen Institute of Parallel and Distributed Systems Shanghai Jiao Tong UniversityShanghai 200240China

Persistent indexing structures are proposed in response to emerging non-volatile memory(NVM)to provide high performance yet durable ***,due to the lack of real NVM hardware,many prior persistent indexing structures were evaluated via emulation,which varies a lot across different setups and differs from the real ***,Intel has released its Optane DC Persistent Memory Module(PMM),which is the first production-ready *** this paper,we revisit popular persistent indexing structures on PMM and conduct comprehensive evaluations to study the performance differences among persistent indexing structures,including persistent hash tables and persistent *** to the evaluation results,we find that Cacheline-Conscious Extendible Hashing(CCEH)achieves the best performance among all evaluated persistent hash tables,and Failure-Atomic ShifT B+-Tree(FAST)and Write Optimal Radix Tree(WORT)perform better than other ***,we find that the insertion performance of hash tables is heavily influenced by data locality,while the insertion latency of trees is dominated by the flush *** also uncover that no existing emulation methods accurately simulate PMM for all the studied data ***,we provide three suggestions on how to fully utilize PMM for better performance,including using clflushopt/clwb with sfence instead of clflush,flushing continuous data in a batch,and avoiding data access immediately after it is flushed to PMM.

关键词： persistent memory data structure performance Intel Optane DC persistent memory module(PMM)

Optimistic Transaction Processing in Deterministic Database

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Journal of Computer Science & Technology 2020年第2期35卷 382-394页

作者： Zhi-Yuan Dong Chu-Zhe Tang Jia-chen Wang Zhao-Guo Wang hai-bo chen Bin-Yu Zang Institute of Parallel and Distributed Systems Shanghai Jiao Tong UniversityShanghai 200240China

Deterministic databases can improve the performance of distributed workload by eliminating the distributed commit protocol and reducing the contention ***,the current deterministic scheme does not consider the performance scalability within a single *** this paper,we describe a scalable deterministic concurrency control,Deterministic and Optimistic Concurrency Control(DOCC),which is able to scale the performance both within a single node and across multiple *** performance improvement comes from enforcing the determinism lazily and avoiding read-only transaction blocking the *** evaluation shows that DOCC achieves 8x performance improvement than the popular deterministic database system,Calvin.

关键词： deterministic database concurrency control scalability

Analysis of Single-Walled Carbon Nanotubes Using a Chemical bond Element Model

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Chinese Journal of Chemical Physics 2008年第4期21卷 353-360页

作者： Ji-nan Lu hai-bo chen Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China Key Laboratory of Mechanical Behavior and Design of Materials Chinese Academy of Sciences Hefei 230027 China

A three dimensional nano-scale finite element model （FEM）, called the chemical bond element model, is proposed for the simulation of mechanical properties of single-walled carbon nanotubes （SWCNTs） based upon molecular mechanics method. Chemical bonds between carbon atoms are modeled by chemical bond elements. The constants of a sub-stiffness matrix are determined by using a linkage between molecular mechanics and continuum mechanics. In order to evaluate the correctness and performance of the proposed model, simulation was done to determine the influence of nanotube wall thickness, radius and length on the elastic modulus （Young＇s modulus and shear modulus） of SWCNTs. The simulation results show that the choice of wall thickness significantly affects the Young＇s modulus and shear modulus. The force field constants is also very important, because the elastic modulus is sensitive to force field constants and the elastic properties of SWCNT are related to the radii of the tubes. The contribution of length to elastic modulus is insignificant and can be ignored. In comparison with the Young＇s modulus and shear modulus reported in the literature, the presented results agree very well with the corresponding theoretical results and many experimental measurements. Furthermore, if the force constants are properly chosen, the present method could be conveniently used to predict the mechanical behavior of other single-walled nanotubes such as boron nitride nanotubes. The results demonstrate the value of the proposed model as a valuable tool in the study of mechanical behaviors of carbon nanotubes and in the analysis of nanotube-based equipments.

关键词： Single-walled carbon nanotube Finite element method Elastic property Molecular mechanics

Preparation of Sm_2Fe_(17) alloy by reduction-diffusion process

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Rare Metals 2018年第11期37卷 989-994页

作者： hai-bo chen Jing-Wu Zheng Liang Qiao Yao Ying Li-Qiang Jiang Sheng-Lei Che Research Center of Magnetic and Electronic Materials College of Materials Science and Engineering Zhejiang University of Technology

SmFealloy is the intermediate material for the preparation of SmFeNx(x ≈ 3); thus, the synthesis of pure SmFemother alloy is the key to obtaining highperformance SmFeNx. Reduction-diffusion(R-D) is a cost-effective method. In this study, the R-D process of synthesizing SmFewas analyzed by scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), and X-ray fluorescence(XRF). Furthermore, the influences of the tightness of compacted reactants, the compensation amount of SmO,and the particle size of Fe on the formation of SmFewere discussed from the aspects of the three raw *** results show that Sm reduced from SmOreacts with Fe particles to form intermetallic compound SmFedirectly in the R-D reaction process of preparing SmFe;the generation of Sm and its migration to the surface of Fe particles control the reaction rate; a proper tightness of compacted reactants is necessary for ensuring the purity of SmFeproduct; pure SmFecan be obtained when the compensation of SmOis 33 % of the stoichiometry; and the sufficiency of the reaction improves with the decrease in the size of Fe powders under the same reaction condition.

关键词： Sm_2Fe_(17) Reduction-diffusion Rare earth Permanent magnet

SplitPass： A Mutually Distrusting Two-Party Password Manager

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Journal of Computer Science & Technology 2018年第1期33卷 98-115页

作者： Yu-Tao Liu Dong Du Yu-Bin Xia hai-bo chen Bin-Yu Zang Zhenkai Liang Institute of Parallel and Distributed Systems Shanghai Jiao Tong University Shanghai 200240 China School of Computing National University of Singapore Singapore 117417 Singapore

Using a password manager is known to be more convenient and secure than not using one, on the assmnption that the password manager itself is safe. However recent studies show that most popular password managers have security vulnerabilities that may be fooled to leak passwords without users＇ awareness. In this paper, we propose a new password manager, SplitPass, which vertically separates both the storage and access of passwords into two mutually distrusting parties. During login, all the parties will collaborate to send their password shares to the web server, but none of these parties will ever have the complete password, which significantly raises the bar of a successful attack to compromise all of tile parties. To retain transparency to existing applications and web servers, SplitPass seamlessly splits the secure sockets layer （SSL） and transport layer security （TCP） sessions to process on all parties, and makes the joining of two password shares transparent to the web servers. We have implemented SplitPass using an Android phone and a cloud assistant and evaluated it using 100 apps from top free apps in the Android official market. The evaluation shows that SplitPass securely protects users＇ passwords, while incurring little performance overhead and power consumption.

关键词： password manager privacy protection mobile-cloud system

Mercury: Combining Performance with Dependability Using Self-Virtualization

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Journal of Computer Science & Technology 2012年第1期27卷 92-104页

作者： hai-bo chen Feng-Zhe Zhang Rong chen Bin-Yu Zang Pen-Chung Yew School of Software Shanghai Jiaotong UniversityShanghai 200240China Parallel Processing Institute Fudan UniversityShanghai 201203China Institute of Information Science Academia SinicaTaipeiChina

Virtualization has recently gained popularity largely due to its promise in increasing utilization, improving availability and enhancing security. Very often, the role of computer systems needs to change as the business environment changes. Initially, the system may only need to host one operating system and seek full execution speed. Later, it may be required to add other functionalities such as allowing easy software/hardware maintenance, surviving system failures and hosting multiple operating systems. Virtualization allows these functionalities to be supported easily and effectively. However, virtualization techniques generally incur non-negligible performance penalty. Fortunately, many virtualization- enabled features such as online software/hardware maintenance and fault tolerance do not require virtualization standby all the time. Based on this observation, this paper proposes a technique, called Self-virtualization, which provides the operating system with the capability to turn on and off virtualization on demand, without disturbing running applications. This technique enables computer systems to reap most benefits from virtualization without sacrificing performance. This paper presents the design and implementation of Mercury, a working prototype based on Linux and Xen virtual machine monitor. The performance measurement shows that Mercury incurs very little overhead： about 0.2 ms on 3 GHz Xeon CPU to complete a mode switch, and negligible performance degradation compared to Linux.

关键词： dependability performance self-virtualization dynamic virtualization

Microwave-assisted synthesis of α-hydroxy aromatic ketones from α-bromo aromatic ketones in water

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Chinese Chemical Letters 2011年第1期22卷 53-56页

作者： Xiang Liu hai bo chen Zheng Guang Pan Jian He Xu He Xing Li School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai 200237 China Department of Chemistry Shanghai Normal University Shanghai 200234 China

A reaction of α-bromo aromatic ketones in water with microwave irradiation gave the corresponding α-hydroxy aromatic ketones in good yields. The use of microwaves was found to significantly improve yields and shorten the reaction time. This reaction afforded a very clean, convenient method for the synthesis of α-hydroxy aromatic ketones.

关键词： α-Hydroxy aromatic ketones α-Bromo aromatic ketones Microwave irradiation