2010/10/15 ron minnich <rminn...@gmail.com>:
> 2010/10/15 <cinap_len...@gmx.de>:
>> i wonder if making 9p work better over high latency connections is
>> even the right answer to the problem.
>
> The reason I care is that the link from a CPU node to a file server on
> blue gene is high latency. It might as well be cross-country, it's so
> bad.
>
a mere 6 GB/s (at the bottleneck) for folks who don't understand what
Ron's idea of bad is :) In comparison to the torus in both latency
and bandwidth (which with aggregate bandwidth of all links could be
almost an order of magnitude higher bandwidth), the path to persistent
storage is quite bad.
As a point of clarification, its not actually the link that is
currently the main problem, its the software infrastructure we
currently have deployed (since we are opting not to use the production
Blue Gene file servers/service). Although with our desktop extension
model which uses your laptop (or whatever) as part of the file server
namespace -- latency can be quite long (in fact in many cases it is
across the country, and sometimes in a different one).
-eric
