The Page File. Rosereplicator Strategy And Efficiency Analysis

Nowadays, informationization is a highly-developed. With the deep development of the informationization, the data of an enterprise are increasing in exponential way. Though large amounts of data bring the enterprise wealth, the losses resulted from data loss become greater and greater at the same time. And thus, the importance of disaster recovery will loom large accordingly.RoseReplicator4.0 developed by Rose Datasystems Inc. is a disaster recovery product based on file system, and it offers a low-cost and high-efficiency recovery solution. This software could replicate the data in real time or scheduled time to remote target host according to the need of user. In case the host failure or data corruption occurs in local host, data can be recovered by the remote off-site target host. Meanwhile, the remote off-site target host can offer backup service for the local host. When the service of the local host is cut down for certain reasons, the target host will take over its service quickly and continue offering service for the third party. Thus, the service continuity will be ensured to the maximum extent.The thesis is mainly to investigate in the page files'swapping policy of RoseReplicator4.0. The main research contents:(1) Orderliness of the I/O data. The order to get the I/O data from the driver and write them into page file must be right. Meanwhile, while transmiting, the order of I/O data read from the page file must be right too. So that, the orderliness to read and write I/O data can be ensured.(2) Swapping policy of page file. When you have written enough I/O data to make the memory full, you need to replace some page files for free memory, then save these page files to disk. When the needed I/O data is not in memory, you need to replace the corresponding page file from the disk into the memory. The main target is to promote the reading and writing speed of page file, so as to optimize swapping policy, reduce system spending, promote efficiency, and etc.(3) Mergence and synchronization policy of page file. When you have written enough data to make the disk full and there is no space for memory replacement, it should stop writing page files and start merging them. Then sync the modified page file, and delete the files that are not required to sync form page file.