What is the difference between full allocation and compact allocation?
Compact allocation only allocates as much storage as it needs to keep the pieces downloaded so far. This means that pieces will be moved around to be placed at their final position in the files while downloading (to make sure the completed download has all its pieces in the correct place). In full allocation, the entire space that a file needs is allocated as soon as one piece of that file is downloaded, thus decreasing fragmentation. We suggest that our users use full allocation. Deluge uses sparse-files(http://en.wikipedia.org/wiki/Sparse_file) for full allocation, the compact allocation option is only useful on windows-file systems.
Compact allocation only allocates as much storage as it needs to keep the pieces downloaded so far. This means that pieces will be moved around to be placed at their final position in the files while downloading (to make sure the completed download has all its pieces in the correct place). In full allocation, the entire space that a file needs is allocated as soon as one piece of that file is downloaded, thus decreasing fragmentation. We suggest that our users use full allocation. Deluge uses sparse files for full allocation, the compact allocation option is only useful on file systems that don’t support sparse files (such as FAT or HFS+).
