NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
On Wed, May 07, 2014 at 09:02:23AM -0500, Rob Latham wrote:
> i'm not entirely sure what you're asking here. Most parallel I/O
> libraries carry out I/O to different regions of the file
> simultaneously (in parallel), and thereby extract more aggregate
> performance out of the storage system.
>
> for any application using any I/O library, the trickiest part is how
> to decompose your domain over N parallel processes and how to
> describe that decomposition.
To clarify: the way I see it, you can do parallel I/O in three different ways.
The first is to reserve a process which will only deal with I/O and other
process will exchange data to read/write with it.
The second is to have each process read/write independantly.
The third is to aggregate the I/O for several processes to improve performances.
So my question was: in practice, which approach does parallel netCDF use ?
> in strict performance terms -- which in the end is not really the
> be-all end all -- Argonne-Northwestern Parallel-NetCDF will be hard
> to beat, unless you are working with record variables.
Do you speak from personal experience ? I would be very interested in seeing
some data or benchmark about it.
--
Alexis Praga
_________________________________________________________
Ph.D Student
Aviation et Environnement
CERFACS
alexis.praga@xxxxxxxxxx
(33) 05 61 19 31 74
Attachment:
pgprcs1zu7WKc.pgp
Description: PGP signature
netcdfgroup archives: