> In case of WAL per database, the operations done on a shared catalog from a
> backend would need flushing system WAL and database WAL to ensure such
> transaction commit. Otherwise only flushing database WAL would do.
I don't think that is a good idea. If you want databases separated you should
install more than one instance. That gives you way more flexibility.
Imho per database WAL is a deficiency, not a feature.
Andreas
PS: problem with mmap was, that it has no attached process count
