Why does Bridge need to repeatdly recreate previews?

I'm here because I could not view metadata today the way I viewed it ten days ago. It's like the metadata files are gone. 

Ehshitification or crapification, whatever you want to call it, Adobe is a big-time player.

The problem of Bridge re-caching and re-generating previews has been around for years. Many old threads in the forums on the issue, yet Adobe coders seem to remain oblivious. On my Windows 11 system, with 50K images spread over hundreds of sub-folders, the problem has been mostly absent since version 14.

The problem has always been intermittent, and does not affect everyone. So, it's system dependent. I have long held a theory, and shared it with Adobe, but who knows. In order to decide if cache, thumbnails, previews need be generated, the software has only 2, maybe 3 variables to compare - File Name, Date, and maybe some attribute like format or size. But for an attribute to change the date would also change. So really only 2 variables.

You navigate to a folder. The software looks at the files in the folder, then looks it up in the cache. If if does not find the file name in the cache, then generate. If it finds the file name in the cache, is the cache current? How would the software make that decision? Simply by comparing the date/time (modified) it gets from the operating system (Win, Mac) to the date/time stored in the cache. No match, then generate.

The rub, I suggest, comes from different formats of these 2 date/time fields plus whatever logic is used to convert one of them to the format of the other for comparison. Imagine the date/time of the OS is kept to a fraction of a second, but the date/time in the cache is not. Now imagine that the processing speed of the computer system is slow or delayed at the time Bridge/ACR/Photoshop create or updates the file. So, the delay or rounding make the date/time stored in the cache slightly different from the the date in the OS. Next time Bridge looks at the file the dates won't match, so Volia!, regeneration.

That would explain why the problem is intermittent and does not affect everyone.

P.S. Arghhhh!!! To make this post I discovered Adobe has changed the forum name. "forums.adobe.com" no longer exists. Now it's community.adobe.com. So, all bookmarks to old threads are lost.

I think it's the fact that there are large performance differences between ADOBE versions, which is extremely irresponsible behavior on the part of the engineers, and even a small change in the sub-codename can make a big difference.
I'm using version 12.0.3 now, you can try this version

The best way I have found to generate cache/index folders is do a search (Edit->Find) and check box boxes. Search through your top-level image folder and let Bridge process everything.

Also, you can purge cache for a specific folder if you are having problems with it.

Hi,

Thank you for your feedback.

Could you share the Bridge version and details of the OS with which you are facing this issue?

Regards,

Bridge Team