[Beowulf] GlusterFS 1.2-BENKI (GNU Cluster File System) - Announcement

[Mark Hahn]

>> nice graph.  but how does it look if you compare a single glusterfs
>> brick with a single NFS brick?
>
> The purpose of glusterfs has never been to beat NFS in a point to point
> throughput competition,

sure.  but my point is that comparing some large number of servers 
under protocol X to a single server under protocol Y is not all 
that meaningful.

> since in real world there are a lot of requests
> happening in parallel and it is more important to achieve a higher
> aggregated bandwidth.

surely a single glusterfs brick can handle more than one request at a time,
though...

> That being said, it is worthy to note that glusterfs is still better than
> NFS in point-to-point (single NFS brick vs single glusterfs brick).
>
> On Gig/E - both nfs and glusterfs peak on the link speed for read. for write
> glusterfs peaks on the link speed, but nfs did not

that's odd, and indicates that the nfs config you tested was hitting 
disk limits.  and unfortunately, that makes the comparison even less
comprehensible.  looking at the config again, it appears that the node
might have just a single disk, which would make the results quite expected.

> On IB - nfs works only with IPoIB, whereas glusterfs does SDP (and ib-verbs,
> from the source repository) and is clearly way faster than NFS.

"clearly"s like that make me nervous.  to an IB enthusiast, SDP may be 
more aesthetically pleasing, but why do you think IPoIB should be noticably
slower than SDP?  lower cpu overhead, probably, but many people have no
problem running IP at wirespeed on IB/10GE-speed wires...