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openmpi/ompi/mca/osc
Nathan Hjelm 7f4872d483 osc/rdma: performance improvments and bug fixes
This commit is a large update to the osc/rdma component. Included in
this commit:

 - Add support for using hardware atomics for fetch-and-op and single
   count accumulate  when using the accumulate lock. This will improve
   the performance of these operations even when not setting the
   single intrinsic info key.

 - Rework how large accumulates are done. They now block on the get
   operation to fix some bugs discovered by an IBM one-sided test. I
   may roll back some of the changes if the underlying bug in the
   original design is discovered. There appear to be no real
   difference (on the hardware this was tested with) in performance so
   its probably a non-issue. References #2530.

 - Add support for an additional lock-all algorithm: on-demand. The
   on-demand algorithm will attempt to acquire the peer lock when
   starting an RMA operation. The lock algorithm default has not
   changed. The algorithm can be selected by setting the
   osc_rdma_locking_mode MCA variable. The valid values are two_level
   and on_demand.

 - Make use of the btl_flush function if available. This can improve
   performance with some btls.

 - When using btl_flush do not keep track of the number of put
   operations. This reduces the number of atomic operations in the
   critical path.

 - Make the window buffers more friendly to multi-threaded
   applications. This was done by dropping support for multiple
   buffers per MPI window. I intend to re-add that support once the
   underlying performance bug under the old buffering scheme is
   fixed.

 - Fix a bug in request completion in the accumulate, get, and put
   paths. This also helps with #2530.

 - General code cleanup and fixes.

Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>
2018-03-15 14:53:53 -06:00
..
base single_predefined_type with MPI_LB/UB 2017-10-03 19:08:18 -04:00
monitoring Remove inter-dependencies between OSC modules. 2018-02-07 11:52:00 +00:00
portals4 opal/asm: rename existing arithmetic atomic functions 2017-11-30 10:41:22 -07:00
pt2pt opal/asm: rename existing arithmetic atomic functions 2017-11-30 10:41:22 -07:00
rdma osc/rdma: performance improvments and bug fixes 2018-03-15 14:53:53 -06:00
sm osc/sm: fix the osc_free callback 2018-01-31 11:23:21 +09:00
ucx OMPI/OSC/UCX: adding atomic lock for fetch_and_op and compare_and_swap 2018-01-18 00:36:22 +02:00
Makefile.am Revert "Update to sync with OMPI master and cleanup to build" 2016-11-22 15:03:20 -08:00
osc.h fixes for Dave's get/set info code 2017-05-17 01:12:49 -04:00