Distributed hash group-by cooperative processing
US5655080A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1995 |
| Grant date | Aug 5, 1997 |
| Priority date | — |
| Expiry date | Aug 14, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2209/509
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method is provided for parallel and cooperative processing of data in a system wherein a coordinator process cooperates with one or more agent processes to which portions of the data processing function is off loaded. The agent processes read and process the data and accumulate a partial result. Each agent process, responsive to statistics collected on the content of the data processed, returns a partial result of the processing to the coordinator process. These steps are repeated iteratively until the processing has been completed. In a specific application, the performance of data processing systems is improved by speeding up database group-by queries. The group-by operation processing is distributed between the host central processing unit (CPU) and the input/output (I/O) processors (IOPs). Essentially, the IOPs are sent group-by requests to be performed on a set of disk blocks (extents), along with a predicate for tuples to be selected for query. The IOPs build a hash table with entries of the group-by element and a running aggregation function (sum for example). The IOPs retrieve the extents, extract the records, select records using the predicate specified, enter the elemen…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.