An implementation of R. Rabenseifner's algorithm for MPI_Iallreduce.
This algorithm is a combination of a reduce-scatter implemented with recursive vector halving
and recursive distance doubling, followed either by an allgather.
Limitations:
-- count >= 2^{\floor{\log_2 p}}
-- commutative operations only
-- intra-communicators only
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
Implements recursive doubling algorithm for MPI_Iallgather.
The algorithm can be used only for power-of-two number of processes.
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
An implementation of R. Rabenseifner's algorithm for MPI_Ireduce.
This algorithm is a combination of a reduce-scatter implemented with recursive vector halving
and recursive distance doubling, followed either by a gather.
Limitations:
-- count >= 2^{\floor{\log_2 p}}
-- commutative operations only
-- intra-communicators only
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
Implements recursive doubling algorithm for MPI_Iexscan.
The algorithm preserves order of operations so it can be used both
by commutative and non-commutative operations.
The MCA parameter 'coll_libnbc_iexscan_algorithm' was added for dynamic
algorithm selection.
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
Implements recursive doubling algorithm for MPI_Iscan. The algorithm preserves order of operations so it can be used both by commutative and non-commutative operations.
The MCA parameter coll_libnbc_iscan_algorithm was added for dynamic algorithm selection.
Signed-off-by: Mikhail Kurnosov <mkurnosov@gmail.com>
This commit updates the entire codebase to use specific opal types for
all atomic variables. This is a change from the prior atomic support
which required the use of the volatile keyword. This is the first step
towards implementing support for C11 atomics as that interface
requires the use of types declared with the _Atomic keyword.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Because a persistent reuqest does not free its `schedule` object
when the communication completes, the `NBC_Progress` function cannot
determine the completion using `schedule`.
Without this change, a hang occurs when the `NBC_Progress` function
is called recursively through the `NBC_Start_round` function.
Signed-off-by: KAWASHIMA Takahiro <t-kawashima@jp.fujitsu.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>
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>
* 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>
This commit rewrites parts of libnbc to fix issues identified by
coverity and myself. The changes are as follows:
- libnbc function would return invalid error codes (internal to
libnbc) to the mpi layer. These codes names are of the form
NBC_. They do not match up with the error codes expected by the mpi
layer. I purged the use of all these error codes with the exception
of NBC_OK and NBC_CONTINUE in progress. These codes are used to
identify when a request handle is complete.
- Handles and schedules were leaked by all collective routines on
error. A new routine was added to return a collective handle
(NBC_Return_handle).
- Temporary buffers containting in/out neighbors for neighborhood
collectives were always leaked.
- Neigborhood collectives contained code to handle MPI_IN_PLACE which
is never a valid input for the send or receive buffer. Stipped this
code out.
- Files were inconsistently named. Most are nbc_isomething.c but one
was named coll_libnbc_ireduce_scatter_block.c.
- Made the NBC_Schedule "structure" and object so it can be
retained/released. This may enable the use of schedule caching at a
later time. More testing will be needed to ensure the caching code
works. If it doesn't the code should be stripped out completely.
- Added code to simply common case of scheduling send/recv +
barrier.
- Code cleanup for readability.
The code now passes the clang static analyzer.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Use of the old ompi_free_list_t and ompi_free_list_item_t is
deprecated. These classes will be removed in a future commit.
This commit updates the entire code base to use opal_free_list_t and
opal_free_list_item_t.
Notes:
OMPI_FREE_LIST_*_MT -> opal_free_list_* (uses opal_using_threads ())
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
Blocking versions are simple linear algorithms implemented in coll/basic. Non-
blocking versions are from libnbc 1.1.1. All algorithms have been tested with
simple test cases.
cmr=v1.7.4:reviewer=jsquyres
This commit was SVN r29265.
value to signal that the operation of retrieving the element from the free list
failed. However in this case the returned pointer was set to NULL as well, so the
error code was redundant. Moreover, this was a continuous source of warnings when
the picky mode is on.
The attached parch remove the rc argument from the OMPI_FREE_LIST_GET and
OMPI_FREE_LIST_WAIT macros, and change to check if the item is NULL instead of
using the return code.
This commit was SVN r28722.
* Only register the progress function on first call to a non-blocking
collective operation, to try to reduce overall performance impact
* Fix tag management in roll-over case
This commit was SVN r27498.
* Use proper tag space (the negatives below the blocking communicators)
instead of the point-to-point space
* Use the PML interface instead of the MPI interface, since the MPI
interface 1) shouldn't be used by components and 2) doesn't like
negative tags
This commit was SVN r26693.
