Revolving around the core of technology
Caching being enabled makes a world of difference in backup time & server load but there is the risk of changes in files being missed. Due to that I propose a couple things:
1. Option to skip/ignore cache every [x] days.
2. Option to skip cache based on filename, extension, folder
For #1, it just makes sense to "verify" the backup every so often. One way to do that is run a "full" backup. That means skipping the cache for one. I'm not sure on the internals of how Syncrify works but rsync has option to force compare of server with local vs just comparing time/date stamp which is obviously faster at expense of reliability. IMO Both of those should/could be done to "verify" the backup on some given interval, say default to 7 days for example. The frequency could be user setting with some system default.
For #2, it is possible the file date/time do not change or are forced to appear to not have changed (such as touch) when they actually have. #1 above could work around that by forcing a compare on a regular basis but ideally there would be settings where cache is skipped & a full compare is forced if needed. Be it by extension (say .pst files had this) or by path "C:\Data\QuickBooks" etc. Perhaps a simple way to do per folder is have a trigger file that if exists skip caching. C:\Data\Syncrify.SkipCache type thing.
IMO #1 is quite important to trust the integrity of backups especially if caching is enabled. It'd be a "cheap" (as in resources), easy way to give some confidence that the backup is trustworthy. #2 as well but not as likely to be an issue except under special likely rare circumstances.
Thx
Bill