If the "Zip-on-the-Fly" script uses a legacy library or an older version of the Zip extension (like ZipArchive in PHP), it may physically be unable to create a ZIP file larger than 2GB or 4GB. Once the streaming compression hits that byte limit, the archive becomes corrupted. The system detects that the requested total size exceeds the format's capability for a single archive and rejects the request.
When a server compresses files on the fly, it utilizes Random Access Memory (RAM) to buffer the data. It needs to hold chunks of data in memory to compress them effectively before sending them out over the network. If the "Zip-on-the-Fly" script uses a legacy library
(only per-file read buffer). Limitation: Output size ≈ sum of input sizes. Still fails if Content-Length cannot be precomputed. When a server compresses files on the fly,
The error message "Total size of requested files is too large for zip-on-the-fly" typically appears in self-hosted cloud storage systems like Limitation: Output size ≈ sum of input sizes