gianm commented on issue #263: Theta sketch - Concurrent union implementation URL: https://github.com/apache/incubator-datasketches-java/issues/263#issuecomment-508274478 Speaking as a Druid person & adding to @himanshug's comment - there are two main uses for aggregators (whether on- or off-heap) in Druid right now: 1. At indexing time we use aggregators for doing rollup (summarization). Currently this is the on-heap aggregator flavor, but there are some discussions about moving it to the off-heap flavor. This is the single-writer multiple-reader case @himanshug was talking about. 2. At query time we use aggregators for doing group-by, topn, timeseries, etc queries. Depending on the query engine it might be the on-heap or off-heap flavor. Access here is never concurrent, so any overhead to support concurrency would be needless overhead in this case. For most users probably the bulk of CPU time is spend on (2)
---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
