Jump Tables, TLV Footers, and the Real Cost of Reading What You Don't Need You're paying for bytes you never read. A data engineer on a busy pipeline touches dozens of Parquet files a day: schema discovery, predicate pushdown, column pruning, metadata scrapes for a data catalog sync. In each case, the application needs maybe 200 KB of context from a file that is 4 GB on disk. Without a seekable archive format and a jump table to find the right frame, your HTTP client fetches the whole thi...