In view of the fact that most college English teachers in China invest a great deal of time and effort responding to students’ writing, but find students improve so little in their writing skills, I venture to put fo...In view of the fact that most college English teachers in China invest a great deal of time and effort responding to students’ writing, but find students improve so little in their writing skills, I venture to put forward an alternative way of teaching writing in the paper, that is, teaching writing through small group conferencing. Compared with the traditional teaching methods small group conferencing has following advantages: (1) Saving evaluation time; (2) Providing better feedback; (3) Helping students critique their writing, etc. Since many empirical studies and teaching practices demonstrate that small group conferencing is an effective and efficient way of teaching writing, we have good reason to believe that it will become widespread in the college English teaching in China. \;展开更多
为改进传统RAID5机制小写性能低下问题,提出了一种高性能的冗余数据读写机制RMB(RedundancyManagement for RAID5).RMB采用异步冗余校验方法APC(Asynchronous Parity Calculating),对现有RAID5更新算法的关键步骤进行了优化,将统一计算...为改进传统RAID5机制小写性能低下问题,提出了一种高性能的冗余数据读写机制RMB(RedundancyManagement for RAID5).RMB采用异步冗余校验方法APC(Asynchronous Parity Calculating),对现有RAID5更新算法的关键步骤进行了优化,将统一计算校验块的同步操作拆分成同步镜像写更新和异步冗余计算更新.该操作分解了数据与其校验数据更新的紧耦合现状,提升了写操作并发度;通过合并多个版本镜像块写操作减少异或计算操作的次数.通过实验验证表,RMB机制,可将小写性能大幅提高,峰值可达4倍以上.展开更多
为了解决传统RAID5机制小写性能低下问题,设计了一种高性能的冗余管理机制RMR(RedundancyManagement for RAID5).RMR通过异步冗余计算方法APC(Asynchronous Parity Calculating),对传统RAID5写更新机制的关键技术进行了优化,将集中计算...为了解决传统RAID5机制小写性能低下问题,设计了一种高性能的冗余管理机制RMR(RedundancyManagement for RAID5).RMR通过异步冗余计算方法APC(Asynchronous Parity Calculating),对传统RAID5写更新机制的关键技术进行了优化,将集中计算校验块的同步操作分解为同步的并行镜像写操作和异步冗余计算操作.该操作分解了数据与其校验数据更新的紧耦合特性,提高了写操作并发度;通过合并多个版本镜像块写操作减少异或计算操作的次数.测试表明,通过RMR机制,可将小写性能大幅提高,峰值可达4倍以上.展开更多
This paper presents a novel hierarchy cache architecture for the purpose of optimizing IO performance. The main idea of the hierarchy cache is to use a few megabytes of RAM and a pagefile to form a two-level cache arc...This paper presents a novel hierarchy cache architecture for the purpose of optimizing IO performance. The main idea of the hierarchy cache is to use a few megabytes of RAM and a pagefile to form a two-level cache architecture, The pagefile is equivalent to the cache disk in DCD (Disk Caching Disk). The pagefile outperforms data disks, because data are accessed in different units and different ways. Small writes are collected in the RAM cache first, and data will be transferred to the pagefile in large writes later. When the system is idle, it will destage data from the pagefile to data disks. The performance test results show that the hierarchy cache can improve IO performance dramatically for small writes, and the mail server using the hierarchy cache driver can handle transactions about 2.2 times faster than the normal mail server. The hierarchy cache is implemented as a filter driver, so it's transparent to the current Windows 2000/ Windows XP operating system. Key words hierarchy cache - pagefile - small write - disk caching disk - filter driver CLC number TP 311 Foundation item: Supported by the National Natural Science Foundation of China (60273073)Biography: XIE chang-sheng (1945-), male Professor, research direction: storage system, network storage.展开更多
文摘In view of the fact that most college English teachers in China invest a great deal of time and effort responding to students’ writing, but find students improve so little in their writing skills, I venture to put forward an alternative way of teaching writing in the paper, that is, teaching writing through small group conferencing. Compared with the traditional teaching methods small group conferencing has following advantages: (1) Saving evaluation time; (2) Providing better feedback; (3) Helping students critique their writing, etc. Since many empirical studies and teaching practices demonstrate that small group conferencing is an effective and efficient way of teaching writing, we have good reason to believe that it will become widespread in the college English teaching in China. \;
文摘为改进传统RAID5机制小写性能低下问题,提出了一种高性能的冗余数据读写机制RMB(RedundancyManagement for RAID5).RMB采用异步冗余校验方法APC(Asynchronous Parity Calculating),对现有RAID5更新算法的关键步骤进行了优化,将统一计算校验块的同步操作拆分成同步镜像写更新和异步冗余计算更新.该操作分解了数据与其校验数据更新的紧耦合现状,提升了写操作并发度;通过合并多个版本镜像块写操作减少异或计算操作的次数.通过实验验证表,RMB机制,可将小写性能大幅提高,峰值可达4倍以上.
文摘为了解决传统RAID5机制小写性能低下问题,设计了一种高性能的冗余管理机制RMR(RedundancyManagement for RAID5).RMR通过异步冗余计算方法APC(Asynchronous Parity Calculating),对传统RAID5写更新机制的关键技术进行了优化,将集中计算校验块的同步操作分解为同步的并行镜像写操作和异步冗余计算操作.该操作分解了数据与其校验数据更新的紧耦合特性,提高了写操作并发度;通过合并多个版本镜像块写操作减少异或计算操作的次数.测试表明,通过RMR机制,可将小写性能大幅提高,峰值可达4倍以上.
文摘This paper presents a novel hierarchy cache architecture for the purpose of optimizing IO performance. The main idea of the hierarchy cache is to use a few megabytes of RAM and a pagefile to form a two-level cache architecture, The pagefile is equivalent to the cache disk in DCD (Disk Caching Disk). The pagefile outperforms data disks, because data are accessed in different units and different ways. Small writes are collected in the RAM cache first, and data will be transferred to the pagefile in large writes later. When the system is idle, it will destage data from the pagefile to data disks. The performance test results show that the hierarchy cache can improve IO performance dramatically for small writes, and the mail server using the hierarchy cache driver can handle transactions about 2.2 times faster than the normal mail server. The hierarchy cache is implemented as a filter driver, so it's transparent to the current Windows 2000/ Windows XP operating system. Key words hierarchy cache - pagefile - small write - disk caching disk - filter driver CLC number TP 311 Foundation item: Supported by the National Natural Science Foundation of China (60273073)Biography: XIE chang-sheng (1945-), male Professor, research direction: storage system, network storage.
