摘要:
A database management system (DBMS) generates a query execution plan including information representing one or more database (DB) operations necessary for executing a query and executes the query based on the query execution plan. In the execution of the query, the DBMS dynamically generates a task for executing a DB operation and executes the dynamically generated task. The DBMS executes a task in a plurality of threads executed by a processor core.
摘要:
This analysis system analyzes the behavior of a DBMS in a computer system having a computer which executes tasks in parallel and reads data from a database (DB) when executing a query. This analysis system acquires the number of selected rows corresponding to a key value of an index key used in the query, and calculates a model-based predicted degree of processing parallelism of the processing corresponding to the query. The system acquires, from the storage device, event information on an input-output event with respect to the storage medium when the processing corresponding to the query is executed actually, calculates a measured degree of processing parallelism when the processing corresponding to the query is executed actually, based on the event information, and displays information based on the model-based predicted degree of processing parallelism and the measured degree of processing parallelism.
摘要:
A database management system (DBMS) manages a database existing in a second storage device with an access speed lower than that of a first storage device. In an execution of a query, the DBMS dynamically generates tasks two or more executable tasks in parallel. The DBMS generates task start information which is information representing a content of the execution of the task, manages the task start information, and executes a content represented by the task start information by the task. The task start information includes a data address set existing in the second storage device. The DBMS controls movement of the data address sets between the first storage device and the second storage device based on a management state of the task start information. In addition, the DBMS selects the task start information based on whether or not the data address set exists in the first storage device.
摘要:
Provided is a storage system in which a transaction of a database is quiesced, a pair of a first volume and a second volume is split so as to make settings to allow an access to be made only to the database in the first volume, the transaction is then released from the quiescent state, a sparse space is specified in the database stored in the second volume, only the specified sparse space in the second volume is partially reorganized, and the contents of the partially reorganized second volume are copied to the first volume such that the first volume and the second volume are resynchronized with each other to form the pair again.
摘要:
A parallel data processing system includes a parallel data processing execution unit for reading a data from a data set including a first data set that includes a plurality of first data and a second data set that includes a plurality of second data and executing processing. The parallel data processing execution unit (A) reads the first data from the first data set, and acquires a first value from the first data based on first format information acquired from an application, (B) generates one or more threads for respectively reading one or more second data corresponding to the first value from the second data set based on first reference information acquired from the application, (C) executes (A) and (B) on one or more first data in the first data set, and (D) executes a plurality of the threads in parallel.
摘要:
A database management system (DBMS) generates a query execution plan including information indicating one or more database (DB) operations necessary to execute the query. The DBMS dynamically generates a task for executing the DB operation in execution of the query. The DBMS performs a determination processing of simultaneous-task-generation number when newly creating a task. The determination processing of simultaneous-task-generation number is to calculate the number of simultaneous task generation, which is the number of tasks that can be generated simultaneously, based on the number of tasks which can be newly generated, a first memory resource amount which is the amount of memory resources necessary to be allocated per task newly generated, and a second memory resource amount which is the number of memory resources that can be newly allocated. The number of tasks generated dynamically and simultaneously is equal to or smaller than the calculated number of simultaneously generatable tasks.
摘要:
A database management system (DBMS) generates a query execution plan including information indicating one or more database (DB) operations necessary to execute the query. The DBMS dynamically generates a task for executing the DB operation in execution of the query. The DBMS performs a determination processing of simultaneous-task-generation number when newly creating a task. The determination processing of simultaneous-task-generation number is to calculate the number of simultaneous task generation, which is the number of tasks that can be generated simultaneously, based on the number of tasks which can be newly generated, a first memory resource amount which is the amount of memory resources necessary to be allocated per task newly generated, and a second memory resource amount which is the number of memory resources that can be newly allocated. The number of tasks generated dynamically and simultaneously is equal to or smaller than the calculated number of simultaneously generatable tasks.
摘要:
To provide a storage system that carries out database reorganization processing. Provided is a method of reorganizing, upon request from a host computer, a database which is stored in a disk drive of a storage device, the disk drive containing a first volume where the database is stored and a second volume paired with the first volume to store a copy of the database, and the reorganization method comprising the steps of: making a transaction of the host computer quiescent state; splitting the paired first volume and second volume to be accessed the only database in the first volume; releasing the quiescent state of the transaction; reorganizing the second volume; and copying data in the second volume to the first volume to resynchronize and pair the first volume and the second volume with each other.
摘要:
A database management system (DBMS) manages a database existing in a second storage device with an access speed lower than that of a first storage device. In an execution of a query, the DBMS dynamically generates tasks two or more executable tasks in parallel. The DBMS generates task start information which is information representing a content of the execution of the task, manages the task start information, and executes a content represented by the task start information by the task. The task start information includes a data address set existing in the second storage device. The DBMS controls movement of the data address sets between the first storage device and the second storage device based on a management state of the task start information. In addition, the DBMS selects the task start information based on whether or not the data address set exists in the first storage device.
摘要:
A database management system (DBMS) generates a query execution plan including information representing one or more database (DB) operations necessary for executing a query and executes the query based on the query execution plan. In the execution of the query, the DBMS dynamically generates a task for executing a DB operation and executes the dynamically generated task. The DBMS executes a task in a plurality of threads executed by a processor core.