On Jan 23, 2009, at 2:09 PM, Kyle Schochenmaier wrote:
You are spot-on with your assesment of the striping in PVFS2. Each file gets a round-robin striping based on the distribution parameters of its directory. To my knowledge, you cannot set things on a per-file basis, as the distribution is done on a per-directory basis. If I'm wrong, everyone please feel free to flame me ;-)
Distributions are defined on a per-file basis. The attributes on the directory are used as hints on what distribution parameters to use for files when they are created.
There are at least three ways then to accomplish what you're thinking of (different distributions for different files): - use MPI-IO and specify distribution parameters as hints; they will be used to create the file with a specific distribution - change the attributes on the directory before you create a file, so they match what you want - use pvfs2-cp "-s" and "-n" options to specify your desired parameters, copy an empty file, then write your data into the file with whatever app you like
Rob _______________________________________________ Pvfs2-users mailing list [email protected] http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users
