How to make inotify wait when processing multiple files

Question

I am working on a directory syncing program that uses jnotify to check for changes.

The idea is whenever jnotify detects a change, a sync is performed. The problem is that when many files are copied to or modified in a directory, many syncs are performed instead of one large sync.

Ideally if you were to copy 100 large files to directory A, the sync to directory B would not occur until all the files are fully copied to directory A.

I have thought about somehow using a temp directory (A1) to hold files until they are fully copied and then moving them into A1. But this solution does not work well because I am using unison to perform the sync which only sends file deltas - and that is a feature I would like to use and not circumvent.

Perhaps there is a way to use i/jnotify to detect when multiple files are being updated at once?

Answer 1

Here's a suggestion. How about setting up a set on your application and have it collect up "modified" files/etc it would add that file to a set and when the number of files exceed a certain amount of number, say 100, you would then do a sync. It would also be a good idea to set up a timer too if you want it to be reasonable responsive, like if there is no new changes/etc that is being added to the set for X amount of time go ahead and do a sync also.