Conversion from Avro GenericRecords to Beam Rows takes too much time

[damccorm]

While running TPC-DS SQL query 3 on Dataflow with a input dataset of 1TB I noticed the performancew was not good compared with a native version implemented with Raw GenericRecords.

I enabled profiling and noticed that the performance of the Convert transform that converts Avro GenericRecords into Beam Rows is taking too much time, specially for those records that are relatively simple (not nested recordes / logical types or anything complex).

There is definitely something odd that can be improved in this transformation.

Imported from Jira BEAM-12328. Original Jira may contain additional context.
Reported by: iemejia.

[gabry-lab]

any updates here?

[mosche]

Wondering, have you done some more benchmarks @gabrywu ?

There's been some improvements in the area, particularly improving performance of RowWithGetters which is the foundation for most schema providers. The reverse direction is still pending, I'll merge after the next release cut.

Though, actually, having a quick look at the code, this unfortunately doesn't apply to GenericRecords. GenericRecordToRowFn eagerly converts records to rows rather than just wrapping them and delegating field access the way it is done by RowWithGetters. That's absolutely worth improving!