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 system and method for providing a virtual desktop service using a cache server, the system including a host server configured to provide the virtual desktop service to a user's device using a virtual machine, a distributed file system configured to store data for the virtual machine, and a cache server configured to, when a request to process data reading is received from the virtual machine inside the host server, pre-read a data segment for the requested process of data reading from the distributed file system and store the pre-read data segment in a cache, and perform the process of data reading using the cache.

Abstract: Disclosed herein is a distributed file system using a torus network. The distributed file system includes multiple servers. The location of a master server may be determined to shorten the latency of data input/output. The location of the master server may be determined such that the distance between the master server and a node farthest away from the master server, among nodes, is minimized. When the location of the master server is determined, the characteristics of the torus network and the features of a propagation transmission scheme may be taken into consideration.

Abstract: Disclosed herein are a torus network-based file access path selection method for a distributed file system and an apparatus for the method. The file access path selection method includes acquiring, by a client, layout information about a file desired to be accessed, searching multiple data servers for an object data server based on the layout information, and determining a file access pattern based on a file access location and a size of the file, and setting any one of a shortest path for accessing the object data server and a secondary path having a hop count increased by one hop from that of the shortest path, as an access path to the object data server in consideration of the file access pattern and a bandwidth utilization rate for a network address located on the shortest path.

Abstract: Disclosed herein are a method for automatically allocating IP addresses for a distributed storage system in a large-scale torus network and an apparatus for the method. The method for automatically allocating IP addresses includes acquiring neighboring-node information from multiple storage nodes that constitute the system; generating torus network topology for the multiple storage nodes by combining the neighboring-node information; generating IP address information through which a position of each of the multiple storage nodes in a structure corresponding to the torus network topology can be identified; and allocating IP addresses to the multiple storage nodes by delivering the IP address information to the multiple storage nodes.

Abstract: Disclosed herein are a method for extending and shrinking a volume of a distributed file system based on a torus network and an apparatus for the same. The method for extending a volume includes searching for a volume neighboring a target volume, the extension of which is requested; determining a direction in which a data server is to be added in consideration of whether the neighboring volume is to be extended; searching for multiple candidate data servers in the direction in which a data server is to be added based on the target volume; and adding any one of the multiple candidate data servers to the target volume in consideration of at least one of a server state and a network communication cost.

Abstract: A distributed file system, based on a torus network, includes a center node and one or more storage nodes. The center node encodes data when the data is received from a client. The one or more storage nodes receive data blocks or parity blocks from the center node and store the data blocks or parity blocks.

Abstract: A distributed storage server includes a plurality of data server devices and a plurality of metadata server devices. The metadata server devices store metadata associated with data which is distributively stored in the data server devices. A selected metadata server device checks whether a dangling directory occurs by performing a rename operation, based on information associated with a full path of a parent directory of a source and a full path of a parent directory of a target included in a request of the rename operation. When it is determined that the dangling directory does not occur, the selected metadata server device processes transactions directed to the metadata such that the rename operation is performed. The checking whether the dangling directory occurs is performed before a transaction period for processing the transactions.

Abstract: A distributed file system based on a torus network includes a plurality of metadata servers configured to store metadata of files, a plurality of data servers configured to divide data and store the divided data in a distributed manner, and at least one management server configured to manage the metadata servers and the data servers. The plurality of metadata servers, the plurality of data servers, and the at least one management server are disposed on first to nth planes each of which consists of a plurality of nodes, and the first plane is connected to a plurality of clients through a switch.

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: A corner structure comprises: a fixed member fixed to a corner of a storage tank; a movable member supported on the fixed member so as to be linearly movable; a stop member attached to the fixed member to prevent the movable member from being detached from the fixed member; and a heat insulating member disposed between a sealing wall and a hull. The fixed member comprises a guide portion provided with a guide recessed portion, the movable member comprises a guide protruding portion inserted into the guide recessed portion, and the width and the length of the guide protruding portion are smaller than the width and the length of the guide recessed portion, so that the movable member can be supported on the fixed member to be movable in the longitudinal direction and in the direction perpendicular to the longitudinal direction.

Abstract: A distributed file system based on a torus network includes a center node configured to encode data when the data is received from a client and one or more storage nodes configured to receive data blocks or parity blocks generated by the encoding from the center node and store the data blocks or parity blocks.

Abstract: A file system for supporting a time-series analysis on data of a previous point in time and an operating method thereof. The file system includes a storage server configured to store input data, and provide data suitable for a data request among the stored data, and an analysis server configured to receive the data from the storage server according to an analysis request, and perform an analysis on the received data, and the storage server assigns a time-series attribute to data together with the data, and stores the time-series attribute together with the data.

Abstract: A distributed file system based on a torus network includes a plurality of metadata servers configured to store metadata of files, a plurality of data servers configured to divide data and store the divided data in a distributed manner, and at least one management server configured to manage the metadata servers and the data servers. The plurality of metadata servers, the plurality of data servers, and the at least one management server are disposed on first to nth planes each of which consists of a plurality of nodes, and the first plane is connected to a plurality of clients through a switch.

Abstract: A distributed file system includes metadata servers and data servers. The metadata server includes a selecting unit to select a data server from the data servers, a chunk allocation requesting unit to request that the selected data server perform chunk allocation, a chunk list managing unit to insert a list of chunks transmitted from the data server into a chunk list pool and determine an arrangement method of the chunk list pool, and a chunk fetching unit to fetch available chunk information from the chunk list pool. The data server includes a receiving unit to receive request for chunk allocation from the metadata server, a chunk allocating unit to allocate chunks in response to the request for chunk allocation and write a list of chunks based on information about the allocated chunk, and a transmitting unit to transmit the list of chunks to the metadata server.

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: 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 system and method for providing a virtual desktop service using a cache server, the system including a host server configured to provide the virtual desktop service to a user's device using a virtual machine, a distributed file system configured to store data for the virtual machine, and a cache server configured to, when a request to process data reading is received from the virtual machine inside the host server, pre-read a data segment for the requested process of data reading from the distributed file system and store the pre-read data segment in a cache, and perform the process of data reading using the cache.