On Channel Failures, File Fragmentation Policies, and Heavy-Tailed Completion Times

—It has been recently discovered that heavy-tailed completion times can result from protocol interaction even when file sizes are light-tailed. A key to this phenomenon is the use of a restart policy where if the file is interrupted before it is completed, it needs to restart from the beginning. In this paper, we show that fragmenting a file into pieces whose sizes are either bounded or independently chosen after each interruption guarantees lighttailed completion time as long as the file size is light-tailed; i.e., in this case, heavy-tailed completion time can only originate from heavy-tailed file sizes. If the file size is heavy-tailed, then the completion time is necessarily heavy-tailed. For this case, we show that when the file size distribution is regularly varying, then under independent or bounded fragmentation, the completion time tail distribution function is asymptotically bounded above by that of the original file size stretched by a constant factor. We then prov...

• Type: Journal
• Year: 2016
• Where: TON
• Authors: Jayakrishnan Nair, Martin Andreasson, Lachlan L. H. Andrew, Steven H. Low, John C. Doyle
• Keywords: TON 2016