Abstract: Provided herein is a shuffle embedded distributed storage system and method supporting virtual merge, the system and method including a distributed shared storage configured to store a virtual merged file; a plurality of map servers connected to the distributed shared storage via a network, and configured to perform a map function and record a map result data computed as a result of the map function in the distributed shared storage by means of a map result file; and a plurality of reduce servers connected to the distributed shared storage and the map servers via the network, wherein the virtual merged file includes a list of the map result files recorded by the plurality of map servers, and an identifier of a reduce server to which the virtual merged file is to be transmitted.

Abstract: Disclosed herein is a distributed file system using a torus network. The distributed file system may include multiple servers. The multiple servers are connected with each other through an n-dimensional torus network, and each of the multiple servers may be arranged along n-dimensional axes. Among the servers in the distributed file system, a server group of an (n?1)-dimensional torus network may be connected to a public network. Different loads of the distributed file system may be distributed based on the axes. Through the distribution, the processing performance of the distributed file system may be improved.

Abstract: Provided herein is a filing system creating and deleting apparatus, comprising an available inode pool in which inodes are to be stored, a file system object creating processor creating an inode allocating request signal in response to a file system creating request from an external resource, an inode allocating processor allocating at least one of inodes stored in the available inode pool in response to the inode allocating request signal, a file system object deleting processor creating an inode deallocating request signal in response to a file system deleting request from the external resource, an inode deleting thread collecting inodes requested to be deleted corresponding to the file system deleting request, and an inode deallocating processor deallocating the inode requested to be deleted from the inode deleting thread, wherein a number of inodes stored in the available inode pool is limited to no more than a maximum inode number in the available inode pool, and the inode requested to be deleted creates

Abstract: A virtual machine host server includes a virtual machine in which a guest operating system is installed and operated, a cache manager for processing at least one of an open request, a close request, and an input/output request for a disk image file of the virtual machine, which is stored in a storage system, and managing a boot workload map and a boot segment, a cache device for caching the boot segment, and a prefetch manager for prefetching the boot segment from the cache device.

Abstract: Disclosed are a method and apparatus for reading data in a distributed file system in which a client and a server are separated. In the method and apparatus, a prefetching operation is performed to provide a continuous read function with high performance even in the distributed file system so that an optimum continuous read function of a local file system within the client may be effectively supported when an application program of the client requests continuous reading on a file (or chunk).

Abstract: Disclosed are an apparatus and a method for distribution processing of data, and a storage server and the apparatus for distribution processing of data includes: a metadata management unit providing metadata information corresponding to data to a metadata server to verify information of an original storage server and one or more copy storage servers to store the data from the metadata server; and a data management unit creating a message including the information on the storage servers verified by the metadata management unit and the data, and transmitting the message to a storage server having a higher priority according to priorities of the storage servers to store the corresponding data.

Abstract: 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.

Abstract: A method of efficiently replicating data stored in data servers in an asymmetric file system is provided. A replication processing apparatus of a network transmits a replication request only to a data server that does not replicate data so that it is possible to reduce replication time of a data block and to extend time-out with reference to a response message transmitted by the data server. In addition, each of the data servers may efficiently transmit copy data to another data server by a pipeline data transmission method.

Abstract: In order to synchronize a file between transmitting and receiving nodes, when a file is changed, a hint provider of the transmitting node provides a change file and change information about the change file as a hint to a change log generator, the change log generator generates a change log with reference to the change file and the hint, and the generated change log is transmitted to the receiving node by a change log transmitter.

Abstract: A method and system that can completely delete garbage data in a distributed network system are provided. Because it is impossible to initially access a data server, data to delete is not deleted, and thus when a garbage file is generated, a generated garbage file can be completely deleted. In this case, by performing a deletion operation of a garbage file in a distributed data server unit, operation efficiency can be maximized.

Abstract: A metadata server of a distributed file system calculates an access frequency of a file and changes a maintaining method of chunks of a data server for dividing data of the file into chunk units to store the chunks in a stripe in accordance with access frequency of the file.

Abstract: There are provided a system and method for providing a virtual desktop service using a cache server. A system for providing a virtual desktop service according to the invention includes a host server configured to provide a virtual desktop service to a client terminal using a virtual machine, a distributed file system configured to store data for the virtual machine, and a cache server that is provided for each host server group having at least one host server, and performs a read process or a write process of data using physically separate caches when the read process or write process of the data is requested from the virtual machine in the host server.

Abstract: A source driving integrated circuit is provided. The source driving integrated circuit includes a source driver area, an electrostatic discharge (ESD) circuit area and a fan-out area. The source driver area includes a plurality of source driver units. The ESD circuit area includes a plurality of ESD units. The fan-out area includes conduction lines for electrically connecting respective ones of the source driver units of the source driver area to ones of the plurality of the ESD units of the ESD circuit area. In a horizontal structure of a semiconductor integrated circuit, the fan-out area at least partially overlaps the ESD circuit area.

Abstract: A replicated file deduplication apparatus generates a hash key of a requested data block, determines whether the same data block as the requested data block exists in data blocks of a replicated image file that is derived from the same golden image file as the requested data block using the hash key of the requested data block, and records, if the same data block as the requested data block exists, information of a chunk in which the same data block as the requested data block is stored at a layout of the requested data block.

Abstract: An apparatus for managing files in a hybrid storage system establishes a file management policy based on a directory unit using files stored in first and second storage devices and manages the files of the first storage device and the second storage device in accordance with the established file management policy based on the directory unit.

Abstract: 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.

Abstract: The present invention relates to a method of improving file write performance and providing availability in a hybrid storage system. When a file writing target server information request signal is received from a client, any one cache server is selected in consideration of storage spaces of cache servers, information about the selected cache server to the client is transmitted so that the client stores the file in the selected cache server. When a duplicate writing target server information request is received from the selected cache server, any one first data server is selected in consideration of storage spaces of respective data servers, information about the selected first data server is transmitted to the cache server so that the cache server stores a duplicate of the file in the first data server. Information about storage of the file and the duplicate is received, and then file metadata is stored.

Abstract: Provided are an apparatus and a method for acquiring a consistent result even if one client accesses any metadata server in a circumstance that the cluster configuring many metadata servers exist. The apparatus as mentioned above includes a deletion file list unit that stores information about a deleted metadata during a predetermined period; and a metadata server selector that selects a metadata server to receive a operation request about a metadata among a plurality of metadata servers based on information from the deletion file list unit.

Abstract: 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.

Abstract: 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.