[Unison-hackers] An idea for faster initial syncs

[Benjamin Pierce]

>> * It's tempting to make this a default behavior -- i.e., to *always* use a
>> dummy fingerprint whenever we encounter a new file.
> 
> Yes, that would also be more consistent.

On reflection, I think it's a bad idea to enable this by default -- too much potential for bad behavior if someone happens to create files on the two replicas with the same length at the same time.

> Another idea would be to automatically fingerprint files with a dummy hash in 
> the background in "spare"/idle time, i.e. while waiting for user input.  IMHO 
> that would get us the best of both worlds: quick initial responses from a 
> user's POV, and proper fingerprints ASAP.

That's a possibility, but I wonder whether people would really want it -- computing all those fingerprints for files that are never looked at can take a LONG time (many many hours) on a big replica.

    - Benjamin