A component with implementation of R. Rabenseifner's algorithm for Reduce and Allreduce.
This algorithm is a combination of a reduce-scatter implemented with recursive vector halving
and recursive distance doubling, followed either by a gather or an allgather.
Current limitations:
-- count >= 2^{\floor{\log_2 p}}
-- commutative operations only
-- intra-communicators onl
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
coll/spacc: Modify implementation to use `ompi_coll_base_sendrecv()`
Replace irecv() + isend() + ompi_request_wait() to ompi_coll_base_sendrecv().
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
since Open MPI now requires a C99, and ptrdiff_t type is part of C99,
there is no more need for the abstract OPAL_PTRDIFF_TYPE type.
Signed-off-by: Gilles Gouaillardet <gilles@rist.or.jp>
- Support MPI-2.2 and MPI-3.0 COLL features.
* `MPI_REDUCE_SCATTER_BLOCK`
* neighborhood collective communication
* nonblocking collective communication
- Add `*_BASE_ARGS` and `*_BASE_ARG_NAMES` for convenience.
- Use parameter names used in the MPI Standard.
Signed-off-by: KAWASHIMA Takahiro <t-kawashima@jp.fujitsu.com>
Memory hooks are now set-up on demand. pml/yalla, mtl/mxm and
coll/hcoll need the memory hooks, so make sure those are installed.
Signed-off-by: Yossi Itigin <yosefe@mellanox.com>
As we changed the ABI (forcing a major release), we can limit
the size of the predefined communicators by moving the collective
structure outside the communicator. This might have a minimal,
but unnoticeable, impact on performance. This approach has been
discussed during the January 2017 devel meeting.
Signed-off-by: George Bosilca <bosilca@icl.utk.edu>
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
* Since we are adding a new function to `mca_coll_base_module_2_1_0_t`
we need to increase the version of the module structure to `2_2_0`.
* Add a comment just above the PREDEFINED_COMMUNICATOR_PAD describing
it's purpose and when it should change. To help future developers
trying to answer the question noted in the comment.
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
* Negative values are parameter errors for neighborhood collectives
- Add checks to the mpi/c interface `MPI_PARAM_CHECK`
* Fix a success check for neighbor_alltoallw with dist_graph
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
Fixes a wrong answer from MPI_Ireduce when the red_sched_chain()
path was taken (which only happens for np<=4 and mesgsize>=64k).
The way libnbc treats MPI_IN_PLACE is to set sbuf == rbuf, and
whether an algorithm will work cleanly or not after that depends on the
details.
In this case the last steps of the algorithm amounted to
(right neighbor is sending us reduction results from ranks 1..n-1)
recv into rbuf from right neighbor
add the contribution from our sbuf into rbuf
this would be fine in general, but if sbuf==rbuf, that recv overwrites
the sbuf. I changed it to recv into a tmpbuf if MPI_IN_PLACE was used.
Signed-off-by: Geoffrey Paulsen <gpaulsen@us.ibm.com>
MPI_Allgatherv with MPI_IN_PLACE reads data from wrong location.
They were locating the MPI_IN_PLACE send buffer as
```c
send_buf = (char*)rbuf;
for (i = 0; i < rank; ++i) {
send_buf += ((ptrdiff_t)rcounts[i] * extent);
}
```
when it should be
```c
send_buf = (char*)rbuf;
send_buf += ((ptrdiff_t)disps[rank] * extent);
```
because disps[] specifies where things are in the v-style buffers.
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
Adds the new API hcoll_conetxt_free that resolves the issues
observed with the ctx cache and group_destroy_notify.
Signed-off-by: Valentin Petrov <valentinp@mellanox.com>
protect the mca_coll_libnbc_component.active_requests list with
the new mca_coll_libnbc_component.lock mutex.
Thanks Jie Hu for the report
Signed-off-by: Gilles Gouaillardet <gilles@rist.or.jp>
- instead of coll_base_comm_get_reqs(2) for irecv/isend, use only
one request allocated in the stack and do a irecv/send
- instead of ompi_request_wait_all(2), simpy ompi_request_wait
Signed-off-by: Gilles Gouaillardet <gilles@rist.or.jp>
* If (legal) non-uniform data type signatures are used in ibcast
then the chosen algorithm may fail on the request, and worst case
it could produce wrong answers.
* Add an MCA parameter that, by default, protects the user from this
scenario. If the user really wants to use it then they have to
'opt-in' by setting the following parameter to false:
- `-mca coll_libnbc_ibcast_skip_dt_decision f`
* Once the following Issues are resolved then this parameter can
be removed.
- https://github.com/open-mpi/ompi/issues/2256
- https://github.com/open-mpi/ompi/issues/1763
Signed-off-by: Joshua Hursey <jhursey@us.ibm.com>
Adds mapping of the MPI Fortran pair types (2INTEGER, 2REAL, 2DBLPREC)
to the corresponding hcoll dtypes.
Signed-off-by: Valentin Petrov <valentinp@mellanox.com>
