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[UDUNITS #TWK-161175]: performance of udunits in parallel program

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  • Subject: [UDUNITS #TWK-161175]: performance of udunits in parallel program
  • Date: Mon, 22 Feb 2016 09:59:25 -0700
Burlen,

What sort of parallel computing do you intend? Multiple processes? Multiple 
threads? Or something else?

If you intend multiple threads, then you should know that the UDUNITS-2 library 
is thread-compatible but not thread-safe. In other words, calls to the 
UDUNITS-2 functions should be guarded by an external mutex.

The library doesn't have the ability to send the unit database that one process 
read to other processes.

The library doesn't have the capability of "compiling-in" the database -- even 
the default database is read from an external XML file.

Please respond with a description of the structure of your parallel computing 
so that I can get a better idea of the fit with the UDUNITS-2 library.

> Hi,
> 
> I am writing a parallel program that is intended to run at a very large
> scale. I would like to use udunits, however I am concerned about the I/O
> problems created by each process loading the .xml file via
> "ut_read_xml(const char* path);" function.
> 
> Is the library smart about parallel operation? does it have a capability
> to read the file on a single process and send the contents to others in
> an mpi job?
> 
> if the answer is no, could you advise how to configure the library so
> that it does no I/O and I can use the default unit system?
> does the library have the capability of compiling the default unit
> system in?
> I only will use the default unit system, xml load capability could be
> disabled completely.
> 
> Thanks
> Burlen


Regards,
Steve Emmerson

Ticket Details
===================
Ticket ID: TWK-161175
Department: Support UDUNITS
Priority: Normal
Status: Closed