[Mpi3-tools] Comments on 2/22 draft

[Marc-Andre Hermanns]

Hi Jeff,

> - 1.3.5: what's the difference between a VARCLASS_UTILIZATION and a
> VARCLASS_RESOURCE?  They both say they're measuring resources in the
> MPI library.  One is "absolute", but I don't know what that means.

VARCLASS_UTILIZATION is the ratio of VARCLASS_RESOURCE and whatever the
maximum of that variable is.

Example:
Consider a queue for incoming messages with place for 10 messages.

With 2 messages currently being in the queue, you would get

VARCLASS_UTILIZATION=0.2
VARCLASS_RESOURCE=2

That's how I understand the text, however, I also recommend rephrasing
the text to make it clearer.

> - Why do we need a profiling interface for MPIT?  It's already a tool
> interface.

You could profile your tools, and the MPIT interface. Also, when we open
this to 'the user', which takes the same line as having a Fortran
interface for this, you want time spent here accounted to time spent in
MPI and not in user-code, right?

Best regards,
Marc-Andre
-- 
Marc-Andre Hermanns
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