I built https://github.com/anacrolix/squirrel https://github.com/anacrolix/squirrel for just this purpose. However you might find that batch inserting empty fil

I built https://github.com/anacrolix/squirrel https://github.com/anacrolix/squirrel for just this purpose. However you might find that batch inserting empty files might only be 10x faster or so than creating empty files directly on the filesystem if we are to believe the 10k/s the OP achieved.