Abstract: A computer implemented method includes executing a read-ahead operation by reading data from a tape according to a read plan and storing said data in a ring buffer, determining whether the ring buffer is full, receiving a command indicating an area to be read according to the read plan, and, responsive to receiving the command, reading data from an area of the list of areas to be read corresponding to the command from the ring buffer. The method may further include executing additional read-ahead operations until the ring buffer is full. A computer program product and computer system corresponding to the method are also disclosed.

Abstract: An approach for deleting a file from a primary file system. The approach deletes a directory entry, associated with a file, from an in-memory index associated with a secondary file system. The approach updates an index cache associated with a secondary file system, based on the in-memory index. The approach updates a dirty flag, associated with the secondary file system, to a value of TRUE.

Abstract: In an approach to improve magnetic tape file systems through tape-to-tape copying between nodes on a Linear Tape File System using a cluster-wide named pipe. Embodiments transfer data between a first node and a second node. Additionally, both the first node and the second node implement a parallel shared-disk file system through a data path for node data reading and writing from a shared-disk and to the shared-disk. Further, to transfer data between the first node and the second node, embodiments, write, by the first node, the data for tape-to-tape copy from a first tape drive to the shared-disk, and write, by the second node, the data written from the shared-disk to a second tape drive.

Abstract: An approach for deleting a file from a primary file system. The approach deletes a directory entry, associated with a file, from an in-memory index associated with a secondary file system. The approach updates an index cache associated with a secondary file system, based on the in-memory index. The approach updates a dirty flag, associated with the secondary file system, to a value of TRUE.

Abstract: A computer implemented method includes receiving a list of areas on a subject tape to be read, wherein each area of the list of areas is indicated by a first record number and a last record number corresponding to the area, identifying parameters of a tape drive configured to read the subject tape, wherein the identified parameters of the tape drive contribute to a speed with which the tape drive can read the list of areas, creating a directed graph of the areas on the subject tape based on the identified parameters, wherein the directed graph indicates how long the tape drive will take to read the areas on the subject tape, and determining a fastest reading order of the areas on the subject tape, based, at least in part, on the directed graph and the identified parameters. A computer program product and computer system are also disclosed.

Abstract: A computer-implemented method for unoptimized tape drive read detection is disclosed. The computer-implemented includes determining whether a read order of a trio of related files is consistent with an order in which the trio of related files are stored on a magnetic tape media. The computer-implemented method further includes generating an unoptimized tape drive read warning in response to determining that the read order of the trio of related files is inconsistent with the order in which the trio of related files are stored on the magnetic tape media.

Abstract: A copy operation is received. The copy operation is of one or more files stored on a linear tape file system. The copy operation is performed in a plurality of units of extents of the one or more files.

Abstract: A data transfer system includes a plurality of blockchain nodes having a node storage unit, a data provision server, and a data acquisition server. Each of the blockchain nodes includes an access permission smart contract which records in the node storage unit, as access right information, token validation data, and a token validation smart contract. The data acquisition server has an access right acquisition unit which requests the access permission smart contract to grant an access right to the data; and a data acquisition unit which sends the token to the data provision server and acquires the data. The data provision server includes: an access right validation unit which causes the token validation smart contract to validate the token sent from the data acquisition server; and a data provision unit which provides the data to the data acquisition server when validation by the access right validation unit is successful.

Abstract: An oil-soluble polyester having a weight average molecular weight of 10,000 to 1 000,000, which is a polycondensate prepared by polycondensing the following ingredients (A), (B) and (C):(A) a divalent higher carboxylic acid ingredient,(B) a divalent alcohol ingredient comprising a glycol represented by the following formula:HO--CH.sub.2 --CR.sup.1 R.sup.2 --CH.sub.2 --OHwherein R.sup.1 and R.sup.2 represent a alkyl group, and the sum of carbon numbers in R.sup.1 and R.sup.2 is at least three, and(C) 0.1 to 15% by mole, based on the total of ingredients (A) and (B), of at least one multi-valent ingredient selected from a carboxylic acid with a valency of at least three and an alcohol with a valency of at least three. This oil-soluble polyester is useful as an additive for a lubricating oil.

Abstract: An oil-soluble polyester having a weight average molecular weight of 10,000 to 1,000,000, which is a polycondensate prepared by polycondensing the following ingredients (A) and (B): (A) a dicarboxylic acid ingredient, and (B) a diol ingredient comprising (i) a hindered glycol represented by the following formula: HO--CH.sub.2 --CR.sup.1 R.sup.2 --CH.sub.2 --OH wherein R.sup.1 and R.sup.2 independently represent a linear or branched alkyl group, and (ii) an alkylene glycol having at least 4 carbon atoms in the main chain. This oil-soluble polyester is useful as an additive for a lubricating oil.