[mpas-developers] proposed date/time manager

[Mark Petersen]

Michael,

Thanks for making the requirements document!  It is great to have this 
discussion at such an early stage.

My few comments:
On 2.2.2 Query for notifications, a possible requirement is that the time 
manager needs to test if time+dt exceeds the point, and return the 
remaining time that will be the new dt to reach that point exactly.  This 
is important if we want i/o reported at exactly the requested time for 
variable timestepping.  The other option, for fixed timestepping, is 
to require that all i/o intervals are multiples of the timestep.

On 2.1.1 Set the starting and ending date/time: For long runs we often run 
many queue cycles and use resubmit scripts, so I would want to read the 
start date from the restart file, and have a simulation duration in the 
namelist file.  That can easily be converted to start and end dates, so 
that might be outside of the scope of this document.

Notifications:  It would be convenient to be able to specify a 
notification in ellapsed wall-clock hours, so one could have a restart 
file written after 11:45 in a 12 hour queue.

Mark




On Thu, 17 Feb 2011, Michael Duda wrote:

> Hi, All.
>
> Todd and several of us at NCAR had the chance to meet earlier this
> week to discuss MPAS developments, and one of the items that
> appeared at the top of the list of needs in MPAS is a date/time
> manager. To begin the requirements and design process for this new
> module, I've written a first draft of a summary and requirements
> list based on the MPAS design template that was circulated in
> January; I've attached this draft herewith as a PDF document and
> LaTeX source.
>
> Since I've not consulted with anyone on the requirements in the
> document, I expect that others may have additional items to add,
> or may like to modify the requirements that I've written;
> essentially, I claim no particular ownership of the document, so
> anyone should feel free to comment, modify, or update as
> necessary.
>
> Once we are all satisfied that the stated requirements will meet
> our needs in MPAS, perhaps we could then come up with a design and
> implementation plan to meet those requirements. Also, it occurred
> to me that the time manager might also serve as a test of our
> requirements and design process to see, e.g., whether it is too
> heavy or too light-weight.
>
> Any contributions or comments on the attached document would be
> greatly welcomed!
>
> Cheers,
> Michael
>