Introduce morsel-driven Parquet scan #20529
Description
Is your feature request related to a problem or challenge?
Current parelllization of Parquet scan is bounded by the thread that has the most data / is the slowest to execute, which means in the case of data skew (driven by either larger partitions or less selective filters during pruning / filter pushdown..., variable object store latency), the parallelism will be significantly limited.
Describe the solution you'd like
We can change the strategy by morsel-driven parallelism like described in https://db.in.tum.de/~leis/papers/morsels.pdf.
Doing so is faster for a lot of queries, when there is an amount of skew (such as clickbench) and we have enough row filters to spread out the work.
For clickbench_partitioned / clickbench_pushdown it seems up to ~2x as fast for some queries, on a 10 core machine.
Describe alternatives you've considered
No response
Additional context
No response