questdb / roadmap

QuestDB Public Roadmap
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Write IO optimization to improve data visibility, latency #47

Open ideoma opened 1 year ago

ideoma commented 1 year ago

This is a storage feature to reduce IO when writing out-of-order data to WAL and non-WAL table.

The core of the approach is to automatically spit partitions into smaller parts to reduce the size of the re-written data due to out-of-order write pattern.

If for example the table is daily partitioned, the last partition can appear to be split into multiple parts

2023-03-01 2023-03-01T13 2023-03-01T14 2023-03-01T145004-123409

And then the data rolls to the next partition 2023-03-02, 2023-03-01 is squashed back to single part.