If you
want to access data from one machine on another, then the data has to get to the
execute machine somehow.
If you
do a lot of remote file access, then the data will still pass across the wires,
only in lumps at a time, when you
need
it, rather than all up front.
For
example, if you have a distributed build system and you want to compile a file
called X.c which is 10Mb,
you
can copy the whole file across and then compile it, or you could use a networked
file system so that the
compiler accesses X.c using networked file I/O without
having to copy the whole file. All lines of the file
will
still have to be copied across however, so I am sure if you monitored it that
10Mb of data would have flowed across
the
wire by the end of the execution.
At
least, I am fairly certain thats how it would work for a vanilla universe
job.
I/O
gets more interesting for standard universe jobs, but there are plenty of
experts who can clarify that.
cheers
JK
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