Gallery - optimizations for large collections

[nathhad]

Hello, and thanks for a bunch of great software!

I use Gallery partly to organize and browse a large photo collection (250k+ media items in 750+ folders), and overall it does pretty amazing for something that's out of its usual scope. I have a feeling not many people use it as hard as we do. This collection is synced between several mobile devices and computers with syncthing, too, so not all changes to the collection happen within Gallery.

The main challenge it seems to have (especially on one device I have with slower media card access) is getting through a refresh cycle. Based on what it appears to me to be doing, there are a few things that might be semi-easy (ha, they're all easy right) optimizations that might help it deal with ridiculous collections like this. I don't think any of these things rise at this point to an issue report, but might be worth throwing out here, and if any look worth pursuing, might be worth following a more targeted feature request issue for follow up.

Near as I can tell, it appears Gallery follows the exact same cycle every time, and it appears it may not scan for new folders until near the end. On my slowest device, to find a new folder at this point I usually have to swipe out every app except Gallery, and leave it plugged in with the screen on for an hour at minimum. If it's always following the exact same refresh order if it missed a folder last time, it's probably going to miss it next time too. Some of what I'd suggest you're probably already doing, but just in case.

Suggested refresh order:

• Before anything else, examine the saved path of the "Other location" folder to see if it's a new valid destination that should be cataloged. Handle that first if so.
• Scan the folder tree first to identify any new folders
• Maintain a list of current known folders (app obviously already does this) - but maintain the order of the list and keep track of where in the list the last refresh stopped.
• If new folder(s) detected, focus on adding the new folder to the list first before updating any existing folder
• Check for and remove deleted folders
• Go back to the refresh list and pick back up where the last refresh cycle stopped (with how mobile kills, probably need to just add an update time per each item so it's current when the task killer kicks in), storing name of newest file in each folder, updating thumbnail for that folder as it goes

I think that would take care of everything that actually causes a usability issue with a large collection on a slow device. New folders would be picked up quickly. If file counts and latest thumbnail for existing folders are out of date, that's not a huge deal because your folder still shows up quickly in search for moves. Shorter 5-10 minute periods of use could let it periodically work through the whole folder set in the background.

If anything in there looks useful - let me know and I can help narrow it down to something that makes sense in the issue/feature tracker.

Thanks for all you're doing!