[mpich2-dev] modify mpich2 aggregator

[Rob Latham]

On Thu, Oct 25, 2012 at 12:05:00PM -0500, Jaln wrote:
> Hello everybody,
> 
> I want to evaluate some ideas regarding the I/O aggregators. But have no
> idea how to modify the mpich2 and pvfs2.
> The idea basically is to pass some hint from mpich to pvfs layer.
> What I want to do are:
> 1. For collective read, e.g., in 'ad_read_coll.c', I can see the two-phase
> I/O is implemented there. I want to assign some values for each aggregator,
> e.g., priority value for various aggregators.
> 2. Still for read, I want the assigned value can be seen by the underlying
> file systems' job scheduler. e.g., in pvfs2, src/io/job/job.c,
> then the file system's job scheduler can schedule the aggregators by the
> assigned value.

PVFS2 has a facility for end-to-end tracing, but it's not often used.
I think the pvfs2-developers mailing list might be a good place to
discuss that feature.

You will probably have to modify ad_read_coll to make explicit
PVFS_sys_io calls.  

==rob


-- 
Rob Latham
Mathematics and Computer Science Division
Argonne National Lab, IL USA