I’ve done more research for different sizes of vault. I just created thousands of empty md files to see when the cache is stopped being stored
On 25k files I found that if you close the Obsidian app soon after Indexing complete message disappears and then reopen the app, it starts reindexing from scratch.
If you wait long enough before closing the Obsidian app, the index is saved to the file and reindexing not happening.
Sometimes I get the intermediate result but I don’t know how to get it consistently. Sometimes after reopening the app, only part of the files are being reindexed.
It seems that writing to the IndexedDB is happening asynchronously and UI has no visible indicator of this process, so closing the app before it’s done, loses the index (fully or partially).
In my opinion, you need to show Indexing completed message only after IndexedDB is written down.
I am trying to find the exact amount of files where the indexing is stuck (or maybe takes more time than my patience allows)