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[cluster] Fix oversight in TT key reuse

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In the original code, the position key stored in the TT is used to probe&store TT entries after message passing. Since we only store part of the bits in the TT, this leads to incorrect rehashing. This is fixed in this patch storing also the full key in the send buffers, and using that for hashing after message arrival.

Short testing with 4 ranks (old vs new) shows this is effective:
Score of mpiold vs mpinew: 84 - 275 - 265  [0.347] 624
Elo difference: -109.87 +/- 20.88
This commit is contained in:
Joost VandeVondele
2018-12-04 21:59:07 +01:00
committed by Stéphane Nicolet
parent 2659c407c4
commit 2559c20c6e
4 changed files with 26 additions and 22 deletions
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src/Makefile
+1 -1
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@@ -357,7 +357,7 @@ ifeq ($(OS), Android)
endif
### 3.10 MPI
ifeq ($(CXX),$(filter $(CXX),mpicxx mpic++ mpiCC))
ifeq ($(CXX),$(filter $(CXX),mpicxx mpic++ mpiCC mpicxx.mpich))
mpi = yes
endif