摘要:
Techniques for self-diagnosing performance problems in a database are provided. The techniques include classifying one or more performance problems in a database system. One or more values for quantifying an impact of the one or more performance problems on the database system are then determined. The quantified values are determined based on the performance of operations in the database system. A performance problem based on the one or more quantified values is then determined. A solution for the performance problem is generated and may be outputted.
摘要:
Techniques for self-diagnosing performance problems in a database are provided. The techniques include classifying one or more performance problems in a database system. One or more values for quantifying an impact of the one or more performance problems on the database system are then determined. The quantified values are determined based on the performance of operations in the database system. A performance problem based on the one or more quantified values is then determined. A solution for the performance problem is generated and may be outputted.
摘要:
Techniques for capturing samples of session activity in a database are provided. Session activity for active sessions is recorded at certain times over a time period. Accordingly, a sample of session activity is taken for sessions in a database.
摘要:
Techniques for capturing samples of session activity in a database are provided. Session activity for active sessions is recorded at certain times over a time period. Accordingly, a sample of session activity is taken for sessions in a database.
摘要:
Quantifying the impact of wasteful operations on a database system is provided. One or more operations that are determined to be wasteful are received. The impact of the wasteful operations on performance in a database may then be quantified. The database is monitored to determine when a wasteful operation is being performed. When a wasteful operation is detected, a time value is recorded of the time spent on processing the wasteful operation. The time value is stored and used to quantify an impact of a performance problem in a database. The time value may be stored and associated with other time values that are recorded for the same wasteful operation. Thus, the impact of wasteful operations that are performed and processed in a database may be determined.
摘要:
Quantifying the impact of wasteful operations on a database system is provided. One or more operations that are determined to be wasteful are received. The impact of the wasteful operations on performance in a database may then be quantified. The database is monitored to determine when a wasteful operation is being performed. When a wasteful operation is detected, a time value is recorded of the time spent on processing the wasteful operation. The time value is stored and used to quantify an impact of a performance problem in a database. The time value may be stored and associated with other time values that are recorded for the same wasteful operation. Thus, the impact of wasteful operations that are performed and processed in a database may be determined.
摘要:
A resource scheduler is provided for allocating a computer system resource to database management system (DBMS) processes. The resource scheduler operates according to resource plans and resource allocation methods. Each plan allocates the resource according to a resource allocation method. During operation of the DBMS, any of the active plans and resource allocation method may be exchanged for alternate plans or resource allocation methods. The resource scheduler enforces an emphasis resource allocation method in which processor time is allocated in percentages to groups of database processes groupified according to common execution requirements. A selected plan includes multiple process groups and/or sub-plans. The resource scheduler allocates processor time in multiple levels among the sub-plans and groups of database processes. Database processes are automatically switched between the groups of a plan according to switch criteria.
摘要:
One embodiment of the present invention provides a resource scheduler for allocating a computer system resource, such as memory or mass storage, within a processor, to database management system (DBMS) processes. The resource scheduler operates according to resource plans and resource allocation methods. One or more plans may be configured and loaded with the DBMS. Each plan allocates the resource according to an associated resource allocation method. During operation of the DBMS, any or all of the active plans and resource allocation methods may be exchanged for alternate plans or resource allocation methods. In one embodiment of the invention the resource scheduler enforces a maximum active sessions resource allocation method in which system resources are allocated by limiting the number of active sessions allowed in groups of database processes grouped according to common execution requirements. A selected plan includes multiple process groups and/or sub-plans. The resource scheduler allocates system resources among the sub-plans and groups of database processes according to their associated limits on active session numbers, with sub-plans and groups having higher active session limits getting access to more system resources than sub-plans and groups having lower active session limits.
摘要:
Described herein are techniques for global synchronization that under various scenarios eliminate or defer the acquisition of global locks. In many cases, the need to acquire global locks is eliminated, thereby saving the overhead attendant to processing global locks.
摘要:
Described herein are techniques for global synchronization that under various scenarios eliminate or defer the acquisition of global locks. In many cases, the need to acquire global locks is eliminated, thereby saving the overhead attendant to processing global locks.