The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this pape...The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this paper, we discuss the suitable configuration strategies for caching dynamic content by our experimental results. Considering the system itself can provide support for caching static Web page, such as computer memory cache and disk＇s own cache, we adopt a special pattern that only caches dynamic Web page in some experiments to enlarge cache space. The paper is introduced three different replacement algorithms in our cache proxy module to test the practical effects of caching dynamic pages under different conditions. The paper is chiefly analyzed the influences of generated time and accessed frequency on caching dynamic Web pages. The paper is also provided the detailed experiment results and main conclusions in the paper.展开更多
Content delivery networks are designed to extend the end-to-end transport capability of the Internet to cope with increases in video traffic. For further improvement, bursty request arrivals should be efficiently addr...Content delivery networks are designed to extend the end-to-end transport capability of the Internet to cope with increases in video traffic. For further improvement, bursty request arrivals should be efficiently addressed. As opposed to previous approaches, in which the best client-server pair is individually selected (individual optimization), this paper proposes an algorithm for dealing with simultaneous arrival requests, in which client-server pairs are selected such that all requests receive good service (social optimization). The performance of the proposed algorithm is compared with that of the closest algorithm, an individual optimization algorithm, under the condition that a large number of requests arrive simultaneously. The evaluation criterion is the worst link stress, which is the largest number of streams per link. The numerical results show that the proposed algorithm is effective for large-scale networks and that the closest algorithm does not provide near-optimal solutions, especially when all requests arrive in a small part of the network or when there are many servers.展开更多
基金Supported by the National Natural Science Foun-dation of China (90204008)
文摘The Web cluster has been a popular solution of network server system because of its scalability and cost effective ness. The cache configured in servers can result in increasing significantly performance, In this paper, we discuss the suitable configuration strategies for caching dynamic content by our experimental results. Considering the system itself can provide support for caching static Web page, such as computer memory cache and disk＇s own cache, we adopt a special pattern that only caches dynamic Web page in some experiments to enlarge cache space. The paper is introduced three different replacement algorithms in our cache proxy module to test the practical effects of caching dynamic pages under different conditions. The paper is chiefly analyzed the influences of generated time and accessed frequency on caching dynamic Web pages. The paper is also provided the detailed experiment results and main conclusions in the paper.
文摘Content delivery networks are designed to extend the end-to-end transport capability of the Internet to cope with increases in video traffic. For further improvement, bursty request arrivals should be efficiently addressed. As opposed to previous approaches, in which the best client-server pair is individually selected (individual optimization), this paper proposes an algorithm for dealing with simultaneous arrival requests, in which client-server pairs are selected such that all requests receive good service (social optimization). The performance of the proposed algorithm is compared with that of the closest algorithm, an individual optimization algorithm, under the condition that a large number of requests arrive simultaneously. The evaluation criterion is the worst link stress, which is the largest number of streams per link. The numerical results show that the proposed algorithm is effective for large-scale networks and that the closest algorithm does not provide near-optimal solutions, especially when all requests arrive in a small part of the network or when there are many servers.
文摘首先给出SQL Server全库备份内容的结论,详细列出SQL Server执行全库备份时要执行的各个任务,指出全库备份中不同范围的事务日志备份在执行数据库恢复时的不同作用,列举全库备份操作中容易忽视和混淆的几个注意事项,解释了涉及数据库备份的几个LSN属性,最后以实例说明了SQL Server 2019全库备份的first_lsn和last_lsn产生的过程。
