gruuya commented on issue #9417: URL: https://github.com/apache/arrow-datafusion/issues/9417#issuecomment-1975293258
> Note that in this query, AggregateExec needs a large amount of memory, as we need to keep all the data in memory before sorting/extract top k counts, so relatively high memory usage is to be expected (even though we probably can optimize it further). Ah good point, the cardinality of the input grouped data is indeed very large (~17M). Indeed, a quick google search brought up the following recent paper about high-cardinality top K aggregation: https://www.microsoft.com/en-us/research/publication/cache-efficient-top-k-aggregation-over-high-cardinality-large-datasets/ -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
