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Signed-off-by: Muhammad Haseeb <[email protected]>

cpp/src/io/parquet/writer_impl.cu

@@ -1818,9 +1818,12 @@ auto convert_table_to_parquet_data(table_input_metadata& table_meta,
     auto const table_size  = std::reduce(column_sizes.begin(), column_sizes.end());
     auto const avg_row_len = util::div_rounding_up_safe<size_t>(table_size, input.num_rows());
     if (avg_row_len > 0) {
+      // Ensure `rg_frag_size` is not bigger than size_type::max for default max_row_group_size
+      // value (=uint64::max) to avoid a sign overflow when comparing
       auto const rg_frag_size =
         std::min<size_t>(std::numeric_limits<size_type>::max(),
                          util::div_rounding_up_safe(max_row_group_size, avg_row_len));
+      // Safe comparison as rg_frag_size fits in size_type
       max_page_fragment_size = std::min<size_type>(rg_frag_size, max_page_fragment_size);
     }