The PuzzleFS container filesystem

Posted Sep 26, 2023 8:18 UTC (Tue) by hsiangkao (guest, #123981)
In reply to: The PuzzleFS container filesystem by alexl
Parent article: The PuzzleFS container filesystem

> use a block-chunked approach for downloads, but expand into full-file dedup in the local storage.

Yes, yet in that way, there are more effective backup/restore technologies such as delta compression (frequently discussed in several academic conferences such as ATC) to reduce I/Os than just do content-defined chunking. And not necessary in a real filesystem form to keep such delta compression archival format.

The PuzzleFS container filesystem

Posted Sep 26, 2023 13:52 UTC (Tue) by alexl (subscriber, #19068) [Link]

True, if you don't need the kernel-side to support it you can use arbitrary complex delta approaches to optimize the download.

Also, you can use filesystem level compression (in e.g. btrfs) to compress the files in the backing dir. Or even use reflinks copy create backing files that share some (but not all) blocks.

The sky is the limit, and all these approaches are compatible with using composefs to mount them.