Re: HP opensourced advfs from tru64 and what it means for btrfs

[Evgeniy Polyakov <johnpol@2ka.mipt.ru>]

On Mon, Jun 23, 2008 at 02:21:09PM -0400, Chris Mason (chris.mason@oracle.com) wrote:
> > Sure it is interesting as studing anything new, but there is nothing in
> > advfs which can prevent btrfs from success. Virtually nothing.
> > Advfs is quite old technology built on top of almost 20 years old ideas
> > and hardware, while the former can still be (and likely is) valid,
> > hardware made significant progress.
> 
> In general, the rules that make filesystems go haven't changed in a long
> time.   Disks are slow, ram is faster, and cpu is both infinitely fast
> and important to share with other things running on the hardware.

I believe if things are that simple, you would not start btrfs? :)

> There is a great deal we can learn from any long standing FS in terms of
> layout optimizations, allocation policies and ease of use.

Sure.

> Is there code we can lift 100% from advfs?  It is hard to say for sure,
> but being able to copy policy and basic algorithms is definitely
> important.

There was similar xfs migration story, and still there is btrfs.

I completely agree that there might be some very interesting ideas
implemented, but I believe that all them we could already know about,
and porting theirs implementation into the new FS will not be easy
steps. I fully appreciate advfs became open and belive that it will get
some commnunity support, but I think that we are already behind its
milestone.

-- 
	Evgeniy Polyakov