Modify comm_split to avoid ucp #1649
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ChuckHastings
added
3 - Ready for Review
improvement
cjnolet
requested changes
Jul 17, 2023
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| update_host(&id, d_nccl_ids.data() + offset, 1, stream_); | ||
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| RAFT_CUDA_TRY(cudaStreamSynchronize(stream_)); |
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We should probably use sync_stream() here so that this is more tolerant to failed ranks.
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Updated in latest push
| @@ -140,48 +142,37 @@ class std_comms : public comms_iface { | |||
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| RAFT_CUDA_TRY(cudaStreamSynchronize(stream_)); | |||
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Now that we are using nccl instead of ucp, we should probably avoid any potential deadlocks from dying nccl ranks by using sync_stream here instead of the standard cuda synchronization.
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Updated in latest push
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/merge |
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During testing of a new feature in cugraph I discovered that the method required either MPI comms or UCP. I have an application that has neither.
This PR modifies the
comm_splitimplementation to continue usingallgatherwhen performing the split instead of usingallgatherfollowed by UCP comms.