What's happening when they run UPUpdate, there are log files here:
http://crosquadron.com/ultrapack2/logsExample from one log:
*** Ultrapack 2.01 files (1/3) ****
2010/04/09 21:59:56 [12040] receiving file list
2010/04/09 21:59:57 [7596] >f.st...... JSGME.ini
2010/04/09 22:00:08 [7596] .d..t...... Missions/Campaign/De/
2010/04/09 22:00:08 [7596] .d..t...... Missions/Campaign/Gb/
2010/04/09 22:00:08 [7596] .d..t...... Missions/Campaign/Us/
2010/04/09 22:00:08 [7596] .d..t...... Missions/Net/dogfight/
2010/04/09 22:00:14 [7596] Number of files: 8494
2010/04/09 22:00:14 [7596] Number of files transferred: 1
2010/04/09 22:00:14 [7596]
Total file size: 3.87G bytes2010/04/09 22:00:14 [7596] Total transferred file size: 171 bytes
2010/04/09 22:00:14 [7596] Literal data: 171 bytes
2010/04/09 22:00:14 [7596] Matched data: 0 bytes
2010/04/09 22:00:14 [7596] File list size: 243.97K
2010/04/09 22:00:14 [7596] File list generation time: 0.001 seconds
2010/04/09 22:00:14 [7596] File list transfer time: 0.000 seconds
2010/04/09 22:00:14 [7596]
Total bytes sent: 5142010/04/09 22:00:14 [7596]
Total bytes received: 245.32K2010/04/09 22:00:14 [7596] sent 514 bytes received 245.32K bytes 13.29K bytes/sec
2010/04/09 22:00:14 [7596] total size is 3.87G speedup is 15735.52
You have 3.87G of file to transfer but since almost everything is same transferred size is only:
Total bytes sent + received: 514 + 245.32K