Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementation...Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementations made significant performance degradation on NUMA system because they ignored the slower remote memory access. To solve this problem, a latency-based conflict detection and a forecasting-based conflict prevention method were proposed. Using these techniques, the NUMA aware TM system was presented. By reducing the remote memory access and the abort rate of transaction, the experiment results show that the NUMA aware strategies present good practical TM performance on NUMA system.展开更多
DNS(domain name system) query log analysis has been a popular research topic in recent years. CLOPE, the represented transactional clustering algorithm, could be readily used for DNS query log mining. However, the alg...DNS(domain name system) query log analysis has been a popular research topic in recent years. CLOPE, the represented transactional clustering algorithm, could be readily used for DNS query log mining. However, the algorithm is inefficient when processing large scale data. The MR-CLOPE algorithm is proposed, which is an extension and improvement on CLOPE based on Map Reduce. Different from the previous parallel clustering method, a two-stage Map Reduce implementation framework is proposed. Each of the stage is implemented by one kind Map Reduce task. In the first stage, the DNS query logs are divided into multiple splits and the CLOPE algorithm is executed on each split. The second stage usually tends to iterate many times to merge the small clusters into bigger satisfactory ones. In these two stages, a novel partition process is designed to randomly spread out original sub clusters, which will be moved and merged in the map phrase of the second phase according to the defined merge criteria. In such way, the advantage of the original CLOPE algorithm is kept and its disadvantages are dealt with in the proposed framework to achieve more excellent clustering performance. The experiment results show that MR-CLOPE is not only faster but also has better clustering quality on DNS query logs compared with CLOPE.展开更多
A new scheduling algorithm called deferrable scheduling with time slice exchange (DS-EXC) was proposed to maintain the temporal validity of real-time data. In DS-EXC, the time slice exchange method was designed to fur...A new scheduling algorithm called deferrable scheduling with time slice exchange (DS-EXC) was proposed to maintain the temporal validity of real-time data. In DS-EXC, the time slice exchange method was designed to further defer the release time of transaction instances derived by the deferrable scheduling algorithm (DS-FP). In this way, more CPU time would be left for lower priority transactions and other transactions. In order to minimize the scheduling overhead, an off-line scheme was designed. In particular, the schedule for a transaction set is generated off-line until a repeating pattern is found, and then the pattern is used to construct the schedule on-line. The performance of DS-EXC was evaluated by sets of experiments. The results show that DS-EXC outperforms DS-FP in terms of increasing schedulable ratio. It also provides better performance under mixed workloads.展开更多
This paper presents a new transaction method in terms of which deals are concluded by competitive prices, and indicates its design on multiuser platform, especially the research of synchronization and vieing for power...This paper presents a new transaction method in terms of which deals are concluded by competitive prices, and indicates its design on multiuser platform, especially the research of synchronization and vieing for powers. The system was programmed with SCO FOXBASE 210, C language and Shell. The result of nearly two year′s use proved that the transaction method and its accomplishments are all practicable.展开更多
《中国有色金属学报》和《Transactions of Nonferrous Metals Society of China》(《中国有色金属学报(英文版)》)是中国有色金属学会主办、科学出版社出版的学术期刊。创刊于1991年,主要报道我国有色金属材料、冶金、选矿和化学化工...《中国有色金属学报》和《Transactions of Nonferrous Metals Society of China》(《中国有色金属学报(英文版)》)是中国有色金属学会主办、科学出版社出版的学术期刊。创刊于1991年,主要报道我国有色金属材料、冶金、选矿和化学化工领域的新理论、新技术和新方法。《中国有色金属学报》为月刊,80元/期,全年订价960元。邮发代号:42−218。展开更多
In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can e...In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can enhance the performance of real-time concurrency control mechanism by reducing the number of transactions that might miss their deadlines, and compare the performance of validation concurrency control protocol with that of HP2PL(High priority two phase locking) protocol and OCC-TI-WAIT-50(Optimistic concurrency control-time interval-wait-50) protocol under shared-disk architecture by simulation. The simulation results reveal that the protocol the author presented can effectively reduce the number of transactions restarting which might miss their deadlines and performs better than HP2PL and OCC-TI-WAIT-50. It works well when arrival rate of transaction is lesser than threshold. However, due to resource contention the percentage of missing deadline increases sharply when arrival rate is greater than the threshold.展开更多
Blotting was used to observe cell structures of leaf epidermis cells, and the key method of leaf transaction observation was paraffin section. The concentration, suitable solidification time, melting temperature of ge...Blotting was used to observe cell structures of leaf epidermis cells, and the key method of leaf transaction observation was paraffin section. The concentration, suitable solidification time, melting temperature of gelatin solution and the stain for the gelatin blotting were studied in this research. The results showed that the gelatin blotting could be used to study leaf transaction, it was benefit to make operation easily, and save time, money and so on展开更多
Microsoft DNA(Distributed interNet Application) has p rovided a effective framework of combination PC with the Internet perfectly; In addition, this open framework hase also given the integration of multilingual co mp...Microsoft DNA(Distributed interNet Application) has p rovided a effective framework of combination PC with the Internet perfectly; In addition, this open framework hase also given the integration of multilingual co mponents a strong managing platform. This article has deeply analysed the main technologys of Microsoft DNA, involve COM basic technology, framework of DNA, Microfost UDA(Universal Data Access),com ponent management with COM+, asynchronous communication with MSMQ(M icrosoft Message Queue). In addition, based on a comparative analysise with the C/S(Client/Server) framework, the author has illustrated the excellency of the Multi-tier framework of Microsoft DNA.展开更多
An active queue management（AQM） algorithm called MCHOKeM is presented,which is borrowed from CHOKeW that draws multi-packets at random from the buffer,the multi-packets are compared with an arriving packet and aband...An active queue management（AQM） algorithm called MCHOKeM is presented,which is borrowed from CHOKeW that draws multi-packets at random from the buffer,the multi-packets are compared with an arriving packet and abandoned if they are from the same flow.But MCHOKeM uses multiple virtual queues for different priority packets and enhances the drawing function by adjusting the maximum number of draws based on the current status of virtual queue length.The number of parameters that MCHOKeM needs to maintain is determined by the number of priority levels being supported by the router,which usually has a small limited value.In order to explain the features of MCHOKeM,an analytical model is used.A series of simulation tests to evaluate the performance are given.展开更多
Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on mu...Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on multiprocessor platforms with instance skipping was formulated based on the(m,k)-constrained model.A partitioned scheduling method SC-AD was proposed to solve the problem.SC-AD uses a derived sufficient schedulability condition to calculate the initial value of m for each sensor transaction.It then partitions the transactions among the processors in a balanced way.To further reduce the average relative invalid time of real-time data,SC-AD judiciously increases the values of m for transactions assigned to each processor.Experiment results show that SC-AD outperforms the baseline methods in terms of the average relative invalid time and the average valid ratio under different system workloads.展开更多
基金Projects(61003075, 61170261) supported by the National Natural Science Foundation of China
文摘Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementations made significant performance degradation on NUMA system because they ignored the slower remote memory access. To solve this problem, a latency-based conflict detection and a forecasting-based conflict prevention method were proposed. Using these techniques, the NUMA aware TM system was presented. By reducing the remote memory access and the abort rate of transaction, the experiment results show that the NUMA aware strategies present good practical TM performance on NUMA system.
基金Project(61103046) supported in part by the National Natural Science Foundation of ChinaProject(B201312) supported by DHU Distinguished Young Professor Program,China+1 种基金Project(LY14F020007) supported by Zhejiang Provincial Natural Science Funds of ChinaProject(2014A610072) supported by the Natural Science Foundation of Ningbo City,China
文摘DNS(domain name system) query log analysis has been a popular research topic in recent years. CLOPE, the represented transactional clustering algorithm, could be readily used for DNS query log mining. However, the algorithm is inefficient when processing large scale data. The MR-CLOPE algorithm is proposed, which is an extension and improvement on CLOPE based on Map Reduce. Different from the previous parallel clustering method, a two-stage Map Reduce implementation framework is proposed. Each of the stage is implemented by one kind Map Reduce task. In the first stage, the DNS query logs are divided into multiple splits and the CLOPE algorithm is executed on each split. The second stage usually tends to iterate many times to merge the small clusters into bigger satisfactory ones. In these two stages, a novel partition process is designed to randomly spread out original sub clusters, which will be moved and merged in the map phrase of the second phase according to the defined merge criteria. In such way, the advantage of the original CLOPE algorithm is kept and its disadvantages are dealt with in the proposed framework to achieve more excellent clustering performance. The experiment results show that MR-CLOPE is not only faster but also has better clustering quality on DNS query logs compared with CLOPE.
基金Project(60873030) supported by the National Natural Science Foundation of China
文摘A new scheduling algorithm called deferrable scheduling with time slice exchange (DS-EXC) was proposed to maintain the temporal validity of real-time data. In DS-EXC, the time slice exchange method was designed to further defer the release time of transaction instances derived by the deferrable scheduling algorithm (DS-FP). In this way, more CPU time would be left for lower priority transactions and other transactions. In order to minimize the scheduling overhead, an off-line scheme was designed. In particular, the schedule for a transaction set is generated off-line until a repeating pattern is found, and then the pattern is used to construct the schedule on-line. The performance of DS-EXC was evaluated by sets of experiments. The results show that DS-EXC outperforms DS-FP in terms of increasing schedulable ratio. It also provides better performance under mixed workloads.
文摘This paper presents a new transaction method in terms of which deals are concluded by competitive prices, and indicates its design on multiuser platform, especially the research of synchronization and vieing for powers. The system was programmed with SCO FOXBASE 210, C language and Shell. The result of nearly two year′s use proved that the transaction method and its accomplishments are all practicable.
文摘《中国有色金属学报》和《Transactions of Nonferrous Metals Society of China》(《中国有色金属学报(英文版)》)是中国有色金属学会主办、科学出版社出版的学术期刊。创刊于1991年,主要报道我国有色金属材料、冶金、选矿和化学化工领域的新理论、新技术和新方法。《中国有色金属学报》为月刊,80元/期,全年订价960元。邮发代号:42−218。
文摘In parallel real-time database systems, concurrency control protocols must satisfy time constraints as well as the integrity constraints. The authors present a validation concurrency control(VCC) protocol, which can enhance the performance of real-time concurrency control mechanism by reducing the number of transactions that might miss their deadlines, and compare the performance of validation concurrency control protocol with that of HP2PL(High priority two phase locking) protocol and OCC-TI-WAIT-50(Optimistic concurrency control-time interval-wait-50) protocol under shared-disk architecture by simulation. The simulation results reveal that the protocol the author presented can effectively reduce the number of transactions restarting which might miss their deadlines and performs better than HP2PL and OCC-TI-WAIT-50. It works well when arrival rate of transaction is lesser than threshold. However, due to resource contention the percentage of missing deadline increases sharply when arrival rate is greater than the threshold.
基金Supported by Committee of Nature Science Foundation of Heilongjiang Province (C2005-32)Post-doctoral Science Committee of China (LRB04-217)Scientific Research Start Committee of Northeast Agricultural University
文摘Blotting was used to observe cell structures of leaf epidermis cells, and the key method of leaf transaction observation was paraffin section. The concentration, suitable solidification time, melting temperature of gelatin solution and the stain for the gelatin blotting were studied in this research. The results showed that the gelatin blotting could be used to study leaf transaction, it was benefit to make operation easily, and save time, money and so on
文摘Microsoft DNA(Distributed interNet Application) has p rovided a effective framework of combination PC with the Internet perfectly; In addition, this open framework hase also given the integration of multilingual co mponents a strong managing platform. This article has deeply analysed the main technologys of Microsoft DNA, involve COM basic technology, framework of DNA, Microfost UDA(Universal Data Access),com ponent management with COM+, asynchronous communication with MSMQ(M icrosoft Message Queue). In addition, based on a comparative analysise with the C/S(Client/Server) framework, the author has illustrated the excellency of the Multi-tier framework of Microsoft DNA.
基金supported by the Beijing Natural Science Foundation(4102050)USFC-KOSEF Joint Research Project of China and Korea(60811140343)
文摘An active queue management（AQM） algorithm called MCHOKeM is presented,which is borrowed from CHOKeW that draws multi-packets at random from the buffer,the multi-packets are compared with an arriving packet and abandoned if they are from the same flow.But MCHOKeM uses multiple virtual queues for different priority packets and enhances the drawing function by adjusting the maximum number of draws based on the current status of virtual queue length.The number of parameters that MCHOKeM needs to maintain is determined by the number of priority levels being supported by the router,which usually has a small limited value.In order to explain the features of MCHOKeM,an analytical model is used.A series of simulation tests to evaluate the performance are given.
基金Project(2020JJ4032)supported by the Hunan Provincial Natural Science Foundation of China。
文摘Maintaining temporal consistency of real-time data is important for cyber-physical systems.Most of the previous studies focus on uniprocessor systems.In this paper,the problem of temporal consistency maintenance on multiprocessor platforms with instance skipping was formulated based on the(m,k)-constrained model.A partitioned scheduling method SC-AD was proposed to solve the problem.SC-AD uses a derived sufficient schedulability condition to calculate the initial value of m for each sensor transaction.It then partitions the transactions among the processors in a balanced way.To further reduce the average relative invalid time of real-time data,SC-AD judiciously increases the values of m for transactions assigned to each processor.Experiment results show that SC-AD outperforms the baseline methods in terms of the average relative invalid time and the average valid ratio under different system workloads.
