Need comments about cluster file systems

[Bogdan Costescu]

> Let's say that from a hardware point of view, the Compaq SC solution is
> no more than a alpha cluster with a fast interconnection (QSW).

I think that you miss something here: this is an integrated product. You 
buy it as whole (and pay a lot for it!) and you don't assemble it from 
COTS components as a beowulf cluster (but please don't start another 
"what's a beowulf" discussion :-)).
Now think what the requirements are for PVFS - do you see any mention of 
proprietary network/protocol ? The fact that Compaq knows that it has the 
fast interconnection available makes it much easier for C/P-FS, as you 
already wrote...

> ... uses the QSW NIC to access disks via some file servers, ...

... and of course if you can get NBD to work over the fast interconnect, 
you can the achieve the following...

> ... PFS is able to manage parallel access to file servers, that gives 
> you more throughput of course.

... through RAID1 over NDB.

> Are there some figures about PVFS perfs over SCI and/or Myrinet ?

I've only heard of fast interconnect (not including here Gigabit Ethernet) 
being used for computation as people usually pay the premium for getting a 
low latency device/protocol...

-- 
Bogdan Costescu

IWR - Interdisziplinaeres Zentrum fuer Wissenschaftliches Rechnen
Universitaet Heidelberg, INF 368, D-69120 Heidelberg, GERMANY
Telephone: +49 6221 54 8869, Telefax: +49 6221 54 8868
E-mail: Bogdan.Costescu at IWR.Uni-Heidelberg.De