Some more bugs about AMS_Comm_publish for parallel situation. even the AMS mpi
example can not work.
1) parameter mismatch
asmpub.c line 88
mysetport = *(int *) va_arg(args, int *);
It seems author wants to add another argument as int * to AMS_Comm_publish
function for parallel situation. which not appears in the manual.
I just comment line 88 and line 130-131,
if (mysetport != -1) {
AMS_port = mysetport;
}
2) extra check of port number
asmpub.c line 149
/* Create publisher arguments */
err = AMSP_New_Pub_Arguments(AMS_port, &pub_arg);
CheckErr(err);
AMSP_New_Pub_Arguments function will check the value of AMS_port. A port number
of -1 or 0 will return a error.
3) AMSP_start_publisher_func seems require a port number -1 to force socket
bind function to allocate a new port, which conflict with
AMSP_New_Pub_Arguments check.
nettcppub.c line 66
if (*port == -1)
*port = 0;
at line 94, a bind function is called.
I have to set pub_arg->port = -1 as follows.
if(ctype == MPI_TYPE)
{
pub_arg->care_about_port = 0;
pub_arg->port = -1;
}
else
pub_arg->care_about_port = 1;
Barry, will you please check it?
>
>
> On Aug 6, 2012, at 10:17 PM, "Gong Ding" <gdiso at ustc.edu> wrote:
>
>
>
> > Thanks, Barry. It is really a wonderful tool.
>
>
>
> Thanks
>
>
>
> > PS: The C STRING support of AMS is a bit strange. At very beginning, I
> > can't understand the mechanism of STRING. So I added a CHAR data type to
> > AMS for an alternate of STRING.
>
> >
>
> > Hope the AMS manual have some more detailed description to parallel usage
> > and data types.
>
>
>
> Maybe you can help write it. We really don't have any one
> maintaining/improving the AMS which is a pity. You can access the repository
> with
>
>
>
> hg clone http://petsc.cs.iit.edu/petsc/ams-dev
>
>
>
>
>
> Barry
>
>
>
> >
>
> >
>
> >>
>
> >>
>
> >> On Aug 6, 2012, at 9:36 AM, "Gong Ding" <gdiso at ustc.edu> wrote:
>
> >>
>
> >>
>
> >>
>
> >>> Hi,
>
> >>
>
> >>> I am trying to use AMS as data communicator between computational code
> >>> and user monitor. The AMS works well for serial situation, however, I
> >>> don't know how to use it for parallel environment. The manual has little
> >>> information, too.
>
> >>
>
> >>
>
> >>
>
> >> You need to build AMS with the same MPI that you will use in the
> >> parallel program.
>
> >>
>
> >>
>
> >>
>
> >>>
>
> >>
>
> >>> I'd like to know some thing about data synchronization.
>
> >>
>
> >>> Does AMS process data synchronization in MPI environment automatically?
> >>> Should I call AMS_Comm_publish on every MPI processor, and create memory
> >>> with AMS_Memory_create for my variables on each processor?
>
> >>
>
> >>
>
> >>
>
> >> There are different types of variables you can publish.
>
> >>
>
> >>
>
> >>
>
> >> AMS_Comm_publish() takes an argument AMS_Comm_type which would be
> >> MPI_TYPE like in your case.
>
> >>
>
> >>
>
> >>
>
> >> AMS_Memory_add_field() takes an argument AMS_Shared_type which can be
> >> AMS_COMMON, AMS_DISTRIBUTED or AMS_REDUCED and if it is reduced the
> >> AMS_Reduction_type is AMS_SUM, AMS_MAX, AMS_MIN, or AMS_NONE. See the
> >> manual page for AMS_Memory_add_field() .
>
> >>
>
> >>
>
> >>
>
> >> If AMS_Shared_type is AMS_COMMON then AMS assumes that the values in
> >> those locations are identical on all processes (and it brings over to the
> >> accessor one set of those values), if distributed then each process has an
> >> array of different values (and it brings over all those values, in a long
> >> array, on the accessor) if reduce that it brings back the values after
> >> applying the reduction operator across all the processes; so with sum it
> >> beings back the sum of the values over all the processes.
>
> >>
>
> >>
>
> >>
>
> >>>
>
> >>
>
> >>> If so, the accessor will see how many TCP/IP port? Or accessor only
> >>> communicate with MPI processor 0 and processor 0 will broadcast the
> >>> information to all the others?
>
> >>
>
> >>
>
> >>
>
> >> AMS completely manages the fact there are multiple "publishers", the
> >> accessor transparently handles getting stuff from all the publisher nodes.
>
> >>
>
> >>
>
> >>
>
> >>>
>
> >>
>
> >>> If not, should I only create AMS object on processor 0, and processor 0
> >>> should broadcast what AMS get?
>
> >>
>
> >>
>
> >>
>
> >> Nope, you do not need to do this.
>
> >>
>
> >>
>
> >>
>
> >> Barry
>
> >>
>
> >>
>
> >>
>
> >>>
>
> >>
>
> >>> Gong Ding
>
> >>
>
> >>>
>
> >>
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> >>>
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> >>
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> >>>
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> >>
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> >>>
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> >>
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> >>>
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> >>
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> >>>
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> >>
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> >>>
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> >>
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> >>
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> >>
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> >>
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>
