jt2594838 opened a new pull request, #18276: URL: https://github.com/apache/iotdb/pull/18276
## Description Follow-up to #18264. This PR contains only the lazy primitive-array allocation changes on top of the merged dynamic-bitmap implementation. - Keep `null` placeholders for newly added or unwritten aligned columns and allocate each `PrimitiveArray` only on its first actual write. - Update `TsFileProcessor` memory accounting for lazy primitive-array allocation. - Cover clone/read/WAL/null-tablet paths with unit tests. - Add a 256 MiB integration test that writes 40,000 rows to one aligned measurement and then one row to 1,200 new measurements, preventing the eager-allocation memory failure. - Add a real 1C1D integration performance comparison against a master worktree, including both sparse/lazy-column and fully non-null aligned-tablet workloads, and generate a Markdown report. ## Performance Compared master `91476b0df7` with candidate `b7f846ec98`: | Workload | master | candidate | Result | | --- | ---: | ---: | ---: | | Sparse/lazy columns | 30.598 ms | 14.294 ms | latency -53.29%, throughput +114.07% | | Fully non-null aligned tablets | 123.767 ms | 123.359 ms | +0.33% | ## Tests - AlignedTVList unit tests: 14/14 passed. - 256 MiB low-memory integration test passed (40,000 historical rows, then one row across 1,200 new columns). - 1C1D worktree comparison completed for master and candidate, including the no-null workload. -- 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]
