The text file is unstructured by default, so parsing it requires much more CPU cycles than read the same from a structured file (like a database).
It also doesn’t effective with simultaneous usage (this is the exact reason why we have “database is locked” issues - it’s the file too, which need to be accessed from the different code paths).
So, this idea wouldn’t solve anything but can make it even worse unfortunately, sorry, I always like to read your ideas though 
.
But the idea with append-only records could be a solution, like described here:
this one could be a solution too, we already implemented some kind of that by caching bandwidth in the RAM before flushing to the database.
The journal itself could help too, because it’s exactly the append-only file.
You are correct, it’s the same suggestion, but perhaps more RAM consuming than mine.
I’m with you in that conclusion.
It’s possible that the badger experiments would give us another boost.