These settings are available in system.settings and are autogenerated from source.
s3_upload_part_size_multiply_factor
Type
UInt64
Default
2
Multiply s3_min_upload_part_size by this factor each time s3_multiply_parts_count_threshold parts were uploaded from a single write to S3.
s3_upload_part_size_multiply_parts_count_threshold
Type
UInt64
Default
500
Each time this number of parts was uploaded to S3, s3_min_upload_part_size is multiplied by s3_upload_part_size_multiply_factor.