[Go][Parquet] Inconsistency in RowGroup 'total byte size' field values between implementations

[abbit]

Describe the usage question you have. Please include as many useful details as possible.

parquet.thrift in parquet-format repo describes RowGroup total_byte_size field meaning as

Total byte size of all the uncompressed column data in this row group

This is also the case for C++ implementation of parquet in this repo.

But in case of Go implementation total_byte_size is described as

TotalByteSize is the total size of this rowgroup on disk

The difference between these values can be large, when compression is applied to column chunks.

My question is: Is that intentional inconsistency with format definition and other implementations? And if so, why does this distinction has been made?

Component(s)

Go, Parquet