mayankshriv opened a new pull request #5781: URL: https://github.com/apache/incubator-pinot/pull/5781
Reader context is currently getting eager-initialized during operator initialization. In certain cases this leads to OOM for direct memory as follows: - Consider a case where we have hundreds of segments, but the rows of interest typically are within a much smaller subset of segments. - For cases with large bytes blobs (theta-sketches), the ForwardIndexReaderContext can initialize chunks (from direct-memory) of large size (numRowsPerChunk * lengthOfLargestEntry). This can run into several tens of MBs for theta-sketches. - Under such case, even though the rows of interest are in a small set of segments, the ForwardIndexReader initializes huge chunks for hundreds of segments, which is wasteful. This PR fixes the problem with lazy initialization of the ForwardIndexReaderContext, so that it only gets initialized for segments that have the data. Existing tests are expected to provide coverage for this code change. ## Description Add a description of your PR here. A good description should include pointers to an issue or design document, etc. ## Upgrade Notes Does this PR prevent a zero down-time upgrade? (Assume upgrade order: Controller, Broker, Server, Minion) * [ ] Yes (Please label as **<code>backward-incompat</code>**, and complete the section below on Release Notes) Does this PR fix a zero-downtime upgrade introduced earlier? * [ ] Yes (Please label this as **<code>backward-incompat</code>**, and complete the section below on Release Notes) Does this PR otherwise need attention when creating release notes? Things to consider: - New configuration options - Deprecation of configurations - Signature changes to public methods/interfaces - New plugins added or old plugins removed * [ ] Yes (Please label this PR as **<code>release-notes</code>** and complete the section on Release Notes) ## Release Notes If you have tagged this as either backward-incompat or release-notes, you MUST add text here that you would like to see appear in release notes of the next release. If you have a series of commits adding or enabling a feature, then add this section only in final commit that marks the feature completed. Refer to earlier release notes to see examples of text ## Documentation If you have introduced a new feature or configuration, please add it to the documentation as well. See https://docs.pinot.apache.org/developers/developers-and-contributors/update-document ---------------------------------------------------------------- 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: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org