At 11:35 PM +0100 12/13/00, Manuel Bouyer wrote:
>On Thu, Dec 14, 2000 at 05:06:23AM +1100, Luke Mewburn wrote:
> > The advantage of TCP mounts is that they're more resiliant on LANs or
> > WANs that are not `clean' (i.e, there's some lossage). The reason is
> > because TCP handles the packet assembly and will only retransmit the
> > 1.5K packet that went missing, whereas UDP will retransmit the entire
> > 8K or 32K packet.
>
>This doesn't explain why raw thoughput of TCP mounts is much higther than
>UDP (A solaris client writes at 7MB/s to my NetBSD server with UDP mounts,
>and 11MB/s with TCP).

TCP can play games with ack's to compensate for latency.  UDP can't 
unless the NFS code duplicates that low-level optimization (which I 
doubt).  I would expect large-block operations to be faster over TCP 
if the blocks are larger than the fragment size for the connection in 
use.


Signature held pending an ISO 9000 compliant
signature design and approval process.
h.b.hotz@jpl.nasa.gov, or hbhotz@oxy.edu