Need comments about cluster file systems

[hanzl at noel.feld.cvut.cz]

> > using something like Coda or InterMezzo (for systems where
> > local disks are quicker than network card).
> 
> Ahhh, you are looking for a Named Subsystem that claims to be a Cluster
> File System.  The key to good performance is not exceeding the semantic
> requirements of the application by too much, and the best systems are so
> transparent to the end user that they don't Need A Capitalized Name.
> 
> Our cluster system, for example, uses a specialized whole-file-caching
> filesystem internally. ...

I am looking for any working opensource solution for persistent file
chaching. Please enlighten me if you know any. I looked hard, but I
might have missed something.

> > (For sure others will point you to PVFS, which IMHO makes sense only
> > if network card is quicker than local disk.)
> 
> It's frustrating to hear people talk about how wonderful InterMezzo and
> Lustre _are_, and dismiss PVFS and GFS.  Software that is not quite
> finished is always better and faster than software that already
> exists.  It only loses speed and features when reality looms.
> 
> Talk about vaporware and deployed systems in different categories unless
> you clearly use the future tense.

I quite like PVFS, but I think it does not solve the problem. AFAIK it
can get speed of NIC. I want the speed of local harddisk, which is
much bigger with my hardware. But again, I am ready for any
enlightenment.

I do not know any details about GFS but I will be happy to learn them
if anybody tells me that it can give me what I want.

I did not say Coda or InterMezzo are great solutions. They are just
the only solution I found. Bad ones, yes. Coda is too big, InterMezzo
is not finished.

Another (very good for me) solution would be Caching NFS Client [GJB98]:

 http://www.vergenet.net/linux/redundant_content/talk/html/node4.html
 http://www.cs.washington.edu/homes/gjb/doc/enhanced-linux-nfs-client/index.html

which is unmaintained I think.

So, alltogether, I know no working opensource solution for persistent
file cache working (at least reading) at (nearly) the speed of local
filesystem. I want to have it, thet's why post to this list. I would
be more than happy to hear that GFS or PVFS or ScyldXYZ project
unknown to me can do this. Please let me know.

Regards

Vaclav