> ... but if you create in your own MPI program a different socket,
> then how do you expect to:
>
> 1. communicate using the LAM/MPI functions over your socket ?
> 2. have options set on your socket affect LAM/MPI's socket ?
>
> While you explained a bit more about your project, you still
> didn't
> answer my question related to whether this is a LAM/MPI library
> development or your own program which just uses the LAM/MPI
> library.
>
>
First let me clarify for you that I only want use the MPI library
not modify it, I am just interested in changing the socket size
in a way that your User Guide advises, that is the set the runtime
parameter 'rpi_tcp_sockbuf' to something other than its default
value of '-1'. the question I have is do I set it to '0' or what?
For example:
$ mpirun -ssi rpi_tcp_sockbuf 0 N <executable name>
Does this look ok to you? maybe it should be '=0' or '=1'.
The User Guide says this will cause the user to be able to set
the sockets to a different size in the code itself with 'setsockopt'
to be than the MPI default,i want to see if
it makes a difference to performance. So if I set the
socket size in my program - for example very small value 1024 bytes:
sock = socket( PF_INET, SOCK_STREAM, 0 );
ierr_setsock = setsockopt(sock,0, SO_SNDBUF, &val, 1024);
ierr_setsock2 = setsockopt(sock,0, SO_RCVBUF, &val, 1024);
Is this correct for using with MPI? I mean maybe it is not
supposed to go into the runtime executable itself, and should
be a seperate program?
Anyway, generally I am interested in changing the socket size for
MPI without changes to any MPI itself. Let me know if or how
I misunderstand how this is done, thanks for your all your
help with this.
Maureen
|
