[Parquet] Pre-fetch the next row group when reading parquet files

[alamb]

Is your feature request related to a problem or challenge?

The current Parquet reader has the following pattern:

1. Do I/O to buffer data needed for row groups
2. Decode the data (make RecordBatches)
3. fetching IO for next row group
4. ...

The issue is that this means that after the row group is finished, the CPU will then have to wait for IO before it can begin decoding the next row group. We could use the CPUs more efficiently if we overlapped IO and CPU more

Describe the solution you'd like

Prefetch the next row group (to start the IO) while actively reading the current group

Describe alternatives you've considered

I made a POC of this approach and it looks promising (improves performance locally for very short queries)

• TEST prefetching Row Groups using next_reader API in parquet-rs #18391

Additional context

No response