Memory usage query governor

摘要

Techniques for managing query execution based on memory usage using memory compression. Embodiments may receive a query from a requesting entity and estimate an amount of memory required to execute the query. Upon determining that executing the query would consume an impermissible amount of memory, embodiments may optimize the query by adjusting an amount of memory compression used in executing the query. The optimized query may then be executed to produce a set of query results, which may then be returned to the requesting entity.

主权项

1. A computer-implemented method for managing query execution, comprising:
calculating an estimated memory usage value for executing a query, based at least in part on historical memory usage data relating to previously processed queries, wherein the estimated memory usage value approximates a total amount of memory that will be used when the query is executed, and wherein the estimated memory usage value is calculated before the received query is executed; determining whether executing the query would satisfy a memory consumption condition by comparing the estimated memory usage value with a predetermined threshold amount of memory; and upon determining that executing the query would not satisfy the memory consumption condition, and by operation of one or more computer processors:
determining one or more optimizations for the query adapted to reduce an amount of memory used when the query is executed, such that the memory consumption condition will be satisfied when the query is executed;optimizing the query based on the determined one or more optimizations; andexecuting the optimized query to produce a first set of query results.