- fixing line lengths and some of the comments
- possible bug fix (but I do not think we exposed it in any tests so far)
temporary buffers were allocated as multiples of extent instead of
true_extent + (count -1) * extent.
Everything is still passing Intel tests over tcp and btl mx up to 64 nodes.
This commit was SVN r13956.
Currently 3 algorithms are available:
- non-overlapping, reduce + scatterv, (works for non-commutative operations)
- recursive halving algorithm (copied from basic module)
- ring algorithm (similar to allreduce ring, for large messages)
This commit was SVN r13929.
Algorithm allows user to specify the segment size to be used for computation/communication overlap.
The additional memory requirement for the algorithm is 2 x segment size.
It performed well for (really) large message sizes over MX and it passed intel Allreduce_c and Allreduce_loc_c tests.
This commit was SVN r13832.
- the block sizes are computed in more uniformn way.
The first k blocks may be 1 element larger than the remaining blocks.
The algorithm passed Intel Allreduce_c and Allreduce_loc_c tests, and
IMB-3.2 Allreduce, over TCP and both btl and mtl MX (up to 128 processes).
The algorithm still only supports commutative operations.
This commit was SVN r13738.
outstanding requests can be limited using mca parameters.
The implementation passed Intel, IMB-3.2, and mpi_test_suite tests over
TCP and MX up to 128 processes (64 nodes), on both 32-bit and 64-bit machines.
It is not activated by default, but it should be useful for really large
communicator sizes.
This commit was SVN r13720.
Implementation passed intel: MPI_Reduce_c , MPI_Reduce_loc_c, and MPI_Reduce_user_c tests
over TCP, BTL MX, and MTL MX, as well as, mpi_test_suite Reduce tests (up to 64 nodes).
The algorithm is still not activated by decision function (will be in the near future).
This commit was SVN r13657.
The step used to iterate through buffer was function of true_extent instead of extent.
This may or may not solve ticket #689 because I am still getting failures over btl mx,
but I cannot reproduce failures over mtl mx nor tcp.
This commit was SVN r13459.
- post isends in reverse order of posting irecvs.
if the messages arrive approximately in order, this should
minimize the time spent in matching the requests.
I did not see any performance difference over MX up to 64 nodes, but
the change makes sense and may have some impact when we have (many)
more nodes.
This commit was SVN r13337.
- Allreduce algorithms:
- Recursive doubling is used for small messages (up to 10KB) and can be used for
both commutative and non-commutative operations.
Recursive doubling passed OCC, IMB-3.2, Intel (Allreduce_c, Allreduce_loc_c, and
Allreduce_user_c), mpi_test_suite (Allreduce MIN/MAX, and Allreduce MIN/MAX with
MPI_IN_PLACE) tests on TCP up to 36 nodes and MX up to 64 nodes.
- Ring algorithms performs well for larger messages but cannot be used for
non-commutative operations. It passed the same tests as recursive doubling, except
some of the non-commutative tests in Intel benchmarks Allreduce_loc_c and Allreduce_user_c
(which was expected).
- MPI_Allreduce with new decision function passed all of the tests mentioned above.
- Cleaning up coll_tuned_util. Moving isendrecv to static inline just like sendrecv.
This commit was SVN r13252.
- removing static qualification on ompi_coll_tuned_sendrecv
- adding ompi_coll_tuned_isendrecv function which posts isend and irecv requests
These changes are separate from but necessary for new algorithms I am working on.
This commit was SVN r13161.
- utilizing coll_tuned_util functions
- setting line length to 80.
This implementation uses standard send messages (instead of synchronous ones).
The change improved our performance over MX multiple number of times, however,
there exists a small potential that last message to be sent can be delayed
(until next mpi call, which means potentially infinitely).
If this shows to be a problem, I will modify the algorithms to use synchronous
send as last operation (which will incur performance penalty again).
This commit was SVN r13071.
- in allgather algorithms I replaces irecv-isend-waitall sequence with
call to ompi_coll_tuned_sendrecv
- most of the functions in util code and allgather decision function conform to 80 character line width.
-
This commit was SVN r13069.
components that use configure.m4 for configuration or are always built.
The macro has not been needed since moving to configure types other than
configure.stub
Fixes trac:590
This commit was SVN r13031.
The following Trac tickets were found above:
Ticket 590 --> https://svn.open-mpi.org/trac/ompi/ticket/590
It contains four algorithms:
Bruck (ciel(logP) steps), Recursive Doubling (log(P) for power-of-2 processes), Ring (P-1 steps),
and Neighbor Exchange (P/2 steps for even number of processes).
All algorithms passed occ, IMB-2.3, and intel verification tests from ompi-tests/ for up to 56 processes.
The fixed decision function is based on results collected over MX on the Grig cluster at
the University of Tennessee at Knoxville.
I have also added (and commented out) copy of MPICH2 decision function for allgather
(from their IJHPCA 2005 paper).
This commit was SVN r12910.
- consistent arguments checking (not allowing to select an algorithm which
is not available)
- consistent way of computing the segcount (number of datatypes by segment).
- small cleanups.
- more informative debugging messages.
This commit was SVN r12545.
description. Most of the bcast algorithms can be completed using this
generic function once we create the tree structure. Add all kind of
trees.
There are 2 versions of the generic bcast function. One using overlapping
between receives (for intermediary nodes) and then blocking sends to all
childs and another where all sends are non blocking. I still have to
figure out which one give the smallest overhead.
This commit was SVN r12530.
the default decision functions (for broadcast, reduce and barrier) are based on a
high performance network (not TCP). It should give good performance (really good) for
any network having the following caracteristics: small latency (5 microseconds) and good
bandwidth (more than 1Gb/s).
+ Cleanup of the reduce algorithms, plus 2 new algorithms (binary and binomial). Now most
of the reduce algorithms use a generic tree based function for completing the reduce.
+ Added macros for computing the trees (they are used for bcast and reduce right now).
+ Allow the usage of all 5 topologies.
+ Jelena's implementation of a binary tree that can be used for non commutative operations.
Right now only the tree building function is there, it will get activated soon.
+ Some others minor cleanups.
This commit was SVN r12326.
