摘要:
A cache consistency maintenance procedure to select one of a detection-based cache consistency maintenance procedure optimized for record-based locking and an avoidance-based consistency-based maintenance procedure optimized for table and block-based locking. To support the characteristic of DBMS in which table locking and record locking are consistent to access the same table, the two kinds of the consistency maintenance policies for the same block are processed by a single buffer load process and the two kinds of the consistency maintenance policies are consistent with each other to provide better configuration and performance.
摘要:
A file storage system, a file storing method, and a file searching method. In the file storing method, a single file to be stored is classified into at least one or more objects, and the classified objects are classified into pages with a serial number. One storage device to record the file is selected among a plurality of storage devices connected through a network. One object is allocated to the selected storage device. Pages configuring the file of the object allocated to the selected storage device are stored. When all pages of the file are not stored, the remaining pages are stored by allocating new object to a new storage device. Metadata for managing information about the storage of the file is set. Accordingly, the file can be stored over several disks. In addition, the overall system performance can be increased by setting the file information in the object metadata simply using the least resources.
摘要:
Disclosed is a cloud storage managing a plurality of files, including: a plurality of metadata servers managing a plurality of metadata associated with the plurality of files; a plurality of data servers managing the data of the plurality of files; and a cluster management server managing the plurality of metadata servers and the plurality of data servers.
摘要:
Provided is a hot data management method based on hit counter, which prevents loads from being concentrated on a specific data server due to hot data by efficiently managing the hot data in the asymmetric storage system. Each of data servers of an asymmetric storage system checks hit counter for data stored in the corresponding data server to maintain hit counter information on the data in a latest state. The data server transmits the hit counter information to a metadata server at predetermined intervals. The data server makes or deletes a copy of the data according to the determination of the metadata server whether the data is hot data.
摘要:
Disclosed are an apparatus, a system, and a method for recovering meta data using fragmentary information. The system for recovering meta data includes: a data server storing recovery information for recovering at least one data file and meta data related to each of the data file; and a meta data server storing the meta data related to the data files and receiving the recovery information from the data server when the meta data are lost to recover the lost meta data. By this configuration, the exemplary embodiment of the present invention stably can the lost meta data of the meta data server by using the recovery the meta data and prevent the phenomenon that the meta data collides with each other on the same directory hierarchical structure.
摘要:
Disclosed is a method of calculating parity. The method dividing, by a client system, a file which is to be stored into chunks of a preset size and distributively storing the chunks in a plurality of data servers; sending, by the client system, a data write complete notification message to a metadata server; storing, by the metadata server, a file sent through the data write complete notification message in a recovery queue; and sending, by the metadata server, a random data server a parity calculation request for the file stored in the recovery queue.
摘要:
Provided is a hot data management method based on hit counter, which prevents loads from being concentrated on a specific data server due to hot data by efficiently managing the hot data in the asymmetric storage system. Each of data servers of an asymmetric storage system checks hit counter for data stored in the corresponding data server to maintain hit counter information on the data in a latest state. The data server transmits the hit counter information to a metadata server at predetermined intervals. The data server makes or deletes a copy of the data according to the determination of the metadata server whether the data is hot data.