Thanks you.

Since it is a block device, all files are splitted into chunks of 4 kb (or other value if configured) and from the database perspective there is no difference between large and small files.

For deletions, FoundationDB is able to delete a key range in O(log(n)) time, without using tombstones, and it doesn't use compactions (because it uses B-tree instead of LSM-tree) so I don't think there will be any impact on performance.

Right now TRIM operations are not supported yet, so instead of getting deleted blocks will be marked as "free" by a filesystem and then reused later.