[Beowulf] copying data between clusters

[Joe Landman]

kyron wrote:

> Given I haven't seen single 20TB drives out there yet, I doubt it to be
> the case. I wouldn't throw in NFS as a limiting factor (just yet) as I have

I was commenting on the 30 MB/s figure.  Not whether or not he had 20TB 
attached to it (though if he did ... that would be painful).

> been able to have sustained 250MB/s data transfer rates (2xGigE using
> channel bonding). And this figure is without jumbo frames so I do have some
> protocol overhead loss. The sending server is a PERC 5/i raid with
> 4*300G*15kRPM drives while the receiving well...was loading onto RAM ;)

We are getting sustained 1+GB/s over 10GbE with NFS on a per unit basis. 
  For IB its somewhat faster.  Backing store is able to handle this 
easily.

I think Michael may be thinking about the performance of a single node 
GbE or IDE rather than the necessary r/w performance to populate 20+ TB 
of data for data motion.

> 
> 
> Eric Thibodeau


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