Abstract: Computer-implemented systems and associated operating methods take measurements and landmarks associated with robustness maps and perform tests evaluating the robustness of a database engine's operator implementations and/or query components. The illustrative computer-implemented system comprises logic that receives one or more robustness maps of measured database system performance acquired during database execution in a predetermined range of runtime conditions and uses information from the robustness map or maps to perform regression testing wherein landmarks in the robustness maps are operated upon as a robustness bugs describing conditions under which a predetermined implementation of a database operator or query component degrades in a manner different from a predetermined expected manner.

Abstract: A data processing system includes a query progress analyzer. The database processing system comprises a receiver that receives database queries including a target query directed to a database and a query analyzer. The query analyzer is coupled to the receiver and analyzes progress status of the target query based on comparison of measured target query resource usage to resource usage predicted from a query plan of the target query and measured system resource usage.

Abstract: Computer-implemented and associated operating methods evaluate robustness of a query plan by measuring performance with regard to a range of runtime conditions and producing a map of relative performance of the given query plan when compared with alternative plans for a range of conditions. The computer-implemented system comprises logic that evaluates the selected query plan in comparison to multiple alternative query plans in a predetermined range of runtime conditions that include data characteristics. The logic produces a set of performance measurements and analyzes the measured performance to map performance of the selected query plan in comparison to performance of one or more alternative query plans.

Abstract: According to one embodiment, a method comprises evaluating messages between nodes of a distributed computing environment. Based on timing relationships of the messages, probability of causal links between pairs of messages determined. Based on the determined probability, at least one causal path comprising a plurality of causal links is inferred. Further, an overall probability that the inferred causal path is accurate is determined. In certain embodiments, the overall probability is output for the corresponding causal path to provide an indication of the confidence of the accuracy of such inferred causal path.

Abstract: Computer-implemented systems and associated operating methods implement a fast join for databases which is adapted for usage with flash storage. A system comprises a processor that performs a join of two tables stored in a storage in pages processed in a column orientation wherein column values for all rows on a page are co-located in mini-pages within the page. The processor reduces input/output operations of the join by accessing only join columns and mini-pages containing join results.

Abstract: Computer-implemented systems and associated operating methods create and use an operator map to identify and evaluate database query plan robustness landmarks. The computer-implemented system comprises logic that creates a map evaluating performance of an implementation of a database engine operator during execution under actual operating conditions. The logic measures and maps performance for a selected range of runtime conditions including resource availability and data characteristics.

Abstract: Computer-implemented and associated operating methods evaluate robustness of a query plan by measuring performance with regard to a range of runtime conditions and producing a map of relative performance of the given query plan when compared with alternative plans for a range of conditions. The computer-implemented system comprises logic that evaluates the selected query plan in comparison to multiple alternative query plans in a predetermined range of runtime conditions that include data characteristics. The logic produces a set of performance measurements and analyzes the measured performance to map performance of the selected query plan in comparison to performance of one or more alternative query plans.

Abstract: A method of managing the execution of a workload of transactions of different transaction types on a computer system. Each transaction type may have a different resource requirement. The method may include intermittently, during execution of the workload, determining the performance of each transaction type. A determination may be made of whether if there is an overloaded transaction type in which performance is degraded with an increase in the number of transactions of the transaction type. If there is an overloaded transaction type, the number of transactions of at least one transaction type may be changed.

Abstract: Computer-implemented systems and associated operating methods use atomic query maps to identify and evaluate database query plan robustness landmarks. The computer-implemented system comprises logic that evaluates robustness of a selected atomic query by measuring performance of atomic query execution in a predetermined range of runtime conditions that include data characteristics. The logic produces a set of measurements that can be displayed as one or more performance maps and analyzes the measured performance to identify landmarks indicative of database atomic query performance degradation greater than a predetermined amount.

Abstract: A method of performing a multi-way join of a plurality of database relations includes executing a plurality of pipelined two-way joins with the database relations. Each two-way join has two sequential phases. In the first phase, missing attributes of the input relations that are required to evaluate a joining criterion specific to said two-way join are fetched from a non-volatile memory device, and the input relations are joined according to the criterion. In the second phase, any additional missing attributes of the input relations are fetched from the non-volatile memory device as assigned by an optimization process executed prior to commencing the multi-way join.

Abstract: According to at least one embodiment, a method comprises identifying at least one causal path that includes a node of a distributed computing environment that is of interest. The method further comprises analyzing the identified at least one causal path to determine at least one time interval when the node is active in such causal path, and correlating consumption of a resource by the node to the node's activity in the at least one causal path.

Abstract: Computer-implemented systems and associated operating methods use performance maps created by evaluating robustness of a database operator, query plan, or query to analyze health of a currently-executing query. The computer-implemented system comprises logic that receives one or more robustness maps of measured database system performance acquired during database execution in a predetermined range of runtime conditions. The logic analyzes state of a currently-executing query by locating the query's performance on the robustness maps.

Abstract: An embodiment includes determining user loads and control parameter values. The determining control parameter values are mapped to a performance metric using a function. A constant performance metric is determined where the value of the function calculated at each control parameter value is less than said constant performance metric. An isocontour is defined based on the constant performance metric for each user load. Finally an operating envelope is calculated by correlating the isocontours of multiple user loads.

Abstract: A method of managing the execution of a workload of transactions of different transaction types on a computer system. Each transaction type may have a different resource requirement. The method may include intermittently, during execution of the workload, determining the performance of each transaction type. A determination may be made of whether if there is an overloaded transaction type in which performance is degraded with an increase in the number of transactions of the transaction type. If there is an overloaded transaction type, the number of transactions of at least one transaction type may be changed.

Abstract: A method of determining a multiprogramming level (MPL) for a first computer subsystem may be implemented on a second computer subsystem. The method may include selecting an initial MPL interval having endpoints that bound a local extremum of a computer-system operation variable that is a unimodal function of the MPL. For each interval having a length more than a threshold, operation-variable values for two intermediate MPLs in the interval may be determined. The interval may be diminished by the section of the interval between the one of the intermediate MPLs having an operation-variable value further from the extremum, and the interval endpoint adjacent to the one intermediate MPL. The operating MPL may be set equal to the other intermediate MPL when the interval has a length that is not more than the threshold.

Abstract: A method of performing a multi-way join of a plurality of database relations includes executing a plurality of pipelined two-way joins with the database relations. Each two-way join has two sequential phases. In the first phase, missing attributes of the input relations that are required to evaluate a joining criterion specific to said two-way join are fetched from a non-volatile memory device, and the input relations are joined according to the criterion. In the second phase, any additional missing attributes of the input relations are fetched from the non-volatile memory device as assigned by an optimization process executed prior to commencing the multi-way join.

Abstract: A data processing system includes a query progress analyzer. The database processing system comprises a receiver that receives database queries including a target query directed to a database and a query analyzer. The query analyzer is coupled to the receiver and analyzes progress status of the target query based on comparison of measured target query resource usage to resource usage predicted from a query plan of the target query and measured system resource usage.

Abstract: Computer-implemented systems and associated operating methods implement a fast join for databases which is adapted for usage with flash storage. A system comprises a processor that performs a join of two tables stored in a storage in pages processed in a column orientation wherein column values for all rows on a page are co-located in mini-pages within the page. The processor reduces input/output operations of the join by accessing only join columns and mini-pages containing join results.

Abstract: Computer-implemented systems and associated operating methods take measurements and landmarks associated with robustness maps and perform tests evaluating the robustness of a database engine's operator implementations and/or query components. The illustrative computer-implemented system comprises logic that receives one or more robustness maps of measured database system performance acquired during database execution in a predetermined range of runtime conditions and uses information from the robustness map or maps to prioritize potential changes that improve robustness of a database system implementation wherein landmarks in the robustness map or maps are operated upon as a robustness bug describing conditions under which a predetermined implementation of a database operator or query component degrades in a manner different from a predetermined expected manner.

Abstract: Computer-implemented systems and associated operating methods create and use an operator map to identify and evaluate database query plan robustness landmarks. The computer-implemented system comprises logic that creates a map evaluating performance of an implementation of a database engine operator during execution under actual operating conditions. The logic measures and maps performance for a selected range of runtime conditions including resource availability and data characteristics.