[PVFS2-users] Finding out/changing stripe size

[Robert Latham]

On Thu, Mar 17, 2005 at 12:11:12PM -0700, Martin Cuma wrote:
> I want to make sure that this works. Browsing through the message board 
> archives, I found that PVFS had pvstat utility that would report stripe 
> size. Does PVFS2 have something like that, or, how else could I find 
> distribution parameters for a given file?

On Fri, Mar 18, 2005 at 12:26:10PM -0500, Xiuduan Fang wrote:
> I have the same question. Anyone knows the answer? Thank you for any input.

Martin, Xiuduan:

It might not be exactly the tool you are looking for, but
'pvfs2-fs-dump' can give you an idea:

Here's a bit of the output when run on a 12-server pvfs2 volume (note
that the output of pvfs2-fs-dump is quite verbose.  You might want to
redirect it to a file)

...
File: mpi-io-test2
  handle = 1048569, type = Metafile, server = 0
  handle = 1321528395, type = Datafile, server = 2
  handle = 1651910494, type = Datafile, server = 3
  handle = 1982292593, type = Datafile, server = 4
  handle = 2312674692, type = Datafile, server = 5
  handle = 2643056791, type = Datafile, server = 6
  handle = 2973438890, type = Datafile, server = 7
  handle = 3303820989, type = Datafile, server = 8
  handle = 3634203088, type = Datafile, server = 9
  handle = 3964585187, type = Datafile, server = 10
  handle = 4294967286, type = Datafile, server = 11
  handle = 660764196, type = Datafile, server = 0
  handle = 991146296, type = Datafile, server = 1
...

So, as you can see you can verify that pvfs2 is striping across
multiple servers.  I'm not sure how much work it would be to report
strip size along with handle, type, and server.  We don't now, but
I'll put it on the todo list.

==rob

-- 
Rob Latham
Mathematics and Computer Science Division    A215 0178 EA2D B059 8CDF
Argonne National Labs, IL USA                B29D F333 664A 4280 315B