Re: Question regarding to store file system metadata in database

[Al Viro <viro@ftp.linux.org.uk>]

On Sun, Mar 19, 2006 at 01:50:22PM -0500, Xin Zhao wrote:
> Last, database-based file system is not so complex. As first step, I
> am just proposing to store pathanem-to-inode number in database. So it
> is basically a simple table. We don't really need any fancy features
> provided by db system. That's why I said a reduced  db system is
> enough. So the only difference betwen db-based file system and a
> regular one is that regular file system use directory file to store
> entries, but db-based file system use database to achieve the same
> goal. Looks like db will be a more efficient way. ;-)

Define "database".  And explain how any of existing filesystems manages
to _not_ qualify your definition.

As for "more efficient"...  300 lookups per second is less than an
improvement.  It's orders of magnitude worse than e.g. ext2; I don't
know in which world that would be considered more efficient, but I
certainly glad that I don't live there.