Improve topology detection performance

[artulab]

Motivation

Technical Details

Currently, every helper function that touches the vendor library performs its own init() + shutdown() pair inside a try/finally block. During a single topology discovery this performs very poorly. Now it's calling these functions once lazily when required.

Also improving device_utils.py because unit tests that require no GPU fail when they are running on a machine with no supported AMD GPU as extra.hip package is only available on systems with AMD GPUs.

Test Plan

python -m pytest tests/unittests/test_topology.py -v

Test Result

tests/unittests/test_topology.py::TestFabricInfo::test_empty_fabric_info PASSED                                                         [  1%]
tests/unittests/test_topology.py::TestFabricInfo::test_valid_fabric_info PASSED                                                         [  2%]
tests/unittests/test_topology.py::TestFabricInfo::test_domain_key_comparison PASSED                                                     [  3%]
tests/unittests/test_topology.py::TestFabricInfo::test_empty_domain_keys_do_not_match PASSED                                            [  5%]
tests/unittests/test_topology.py::TestFabricInfo::test_serialization_roundtrip PASSED                                                   [  6%]
tests/unittests/test_topology.py::TestFabricInfo::test_from_dict_missing_keys PASSED                                                    [  7%]
tests/unittests/test_topology.py::TestGPUInfo::test_serialization_roundtrip PASSED                                                      [  8%]
tests/unittests/test_topology.py::TestGPUInfo::test_from_dict_does_not_mutate_input PASSED                                              [ 10%]
tests/unittests/test_topology.py::TestGPUInfo::test_from_dict_missing_fabric PASSED                                                     [ 11%]
tests/unittests/test_topology.py::TestNormalizePCIBusId::test_standard_format PASSED                                                    [ 12%]
tests/unittests/test_topology.py::TestNormalizePCIBusId::test_uppercase PASSED                                                          [ 13%]
tests/unittests/test_topology.py::TestNormalizePCIBusId::test_nvidia_8char_domain PASSED                                                [ 15%]
tests/unittests/test_topology.py::TestNormalizePCIBusId::test_prefix_junk PASSED                                                        [ 16%]
tests/unittests/test_topology.py::TestNormalizePCIBusId::test_no_match PASSED                                                           [ 17%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_nvml_query_helpers_do_not_manage_lifecycle PASSED                    [ 18%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_amdsmi_query_helpers_do_not_manage_lifecycle PASSED                  [ 20%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_nvml_outer_helpers_initialize_and_shutdown PASSED                    [ 21%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_amdsmi_outer_helpers_initialize_and_shutdown PASSED                  [ 22%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_get_gpu_fabric_info_initializes_and_shuts_down_standalone PASSED     [ 23%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_missing_library_fallbacks_preserve_logs PASSED                       [ 25%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_discover_uses_outer_vendor_lifecycle PASSED                          [ 26%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_discover_shuts_down_outer_vendor_lifecycle_on_exception PASSED       [ 27%]
tests/unittests/test_topology.py::TestVendorLibraryLifecycle::test_discover_unknown_vendor_uses_noop_outer_lifecycle PASSED             [ 28%]
tests/unittests/test_topology.py::TestNodeInfo::test_get_link_type_self PASSED                                                          [ 30%]
tests/unittests/test_topology.py::TestNodeInfo::test_get_link_type_out_of_bounds PASSED                                                 [ 31%]
tests/unittests/test_topology.py::TestNodeInfo::test_get_link_type_no_matrix PASSED                                                     [ 32%]
tests/unittests/test_topology.py::TestNodeInfo::test_p2p_access_out_of_bounds PASSED                                                    [ 33%]
tests/unittests/test_topology.py::TestNodeInfo::test_p2p_access_self_always_true PASSED                                                 [ 35%]
tests/unittests/test_topology.py::TestTopologyMap::test_same_rank_is_intra_node PASSED                                                  [ 36%]
tests/unittests/test_topology.py::TestTopologyMap::test_same_node_is_intra_node PASSED                                                  [ 37%]
tests/unittests/test_topology.py::TestTopologyMap::test_same_fabric_different_node_is_fabric PASSED                                     [ 38%]
tests/unittests/test_topology.py::TestTopologyMap::test_no_fabric_is_rdma PASSED                                                        [ 40%]
tests/unittests/test_topology.py::TestTopologyMap::test_node_peers PASSED                                                               [ 41%]
tests/unittests/test_topology.py::TestTopologyMap::test_fabric_domain_peers PASSED                                                      [ 42%]
tests/unittests/test_topology.py::TestTopologyMap::test_rdma_peers PASSED                                                               [ 43%]
tests/unittests/test_topology.py::TestTopologyMap::test_peer_groups_partition_world PASSED                                              [ 45%]
tests/unittests/test_topology.py::TestTopologyMap::test_comm_groups_intra_node PASSED                                                   [ 46%]
tests/unittests/test_topology.py::TestTopologyMap::test_comm_groups_fabric_includes_standalone PASSED                                   [ 47%]
tests/unittests/test_topology.py::TestTopologyMap::test_comm_groups_fabric_domain_group_content PASSED                                  [ 48%]
tests/unittests/test_topology.py::TestTopologyMap::test_comm_groups_fabric_is_not_empty_when_domains_exist PASSED                       [ 50%]
tests/unittests/test_topology.py::TestTopologyMap::test_comm_groups_rdma_is_world PASSED                                                [ 51%]
tests/unittests/test_topology.py::TestTopologyMap::test_heap_plan_completeness PASSED                                                   [ 52%]
tests/unittests/test_topology.py::TestTopologyMap::test_heap_plan_rank4 PASSED                                                          [ 53%]
tests/unittests/test_topology.py::TestTopologyMap::test_heap_plan_no_peer_overlap PASSED                                                [ 55%]
tests/unittests/test_topology.py::TestTopologyMap::test_summary_contains_all_nodes PASSED                                               [ 56%]
tests/unittests/test_topology.py::TestTopologyMap::test_ranks_for_fabric_domain PASSED                                                  [ 57%]
tests/unittests/test_topology.py::TestTopologyMap::test_ranks_for_nonexistent_domain PASSED                                             [ 58%]
tests/unittests/test_topology.py::TestOversubscription::test_num_gpus_is_physical_count PASSED                                          [ 60%]
tests/unittests/test_topology.py::TestOversubscription::test_link_type_by_gpu_id PASSED                                                 [ 61%]
tests/unittests/test_topology.py::TestOversubscription::test_p2p_by_gpu_id PASSED                                                       [ 62%]
tests/unittests/test_topology.py::TestOversubscription::test_all_ranks_are_node_peers PASSED                                            [ 63%]
tests/unittests/test_topology.py::TestIsolationCollapse::test_num_gpus_not_collapsed PASSED                                             [ 65%]
tests/unittests/test_topology.py::TestIsolationCollapse::test_both_ranks_are_node_peers PASSED                                          [ 66%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_no_fabric_all_rdma PASSED                                                   [ 67%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_fabric_peers_empty PASSED                                                   [ 68%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_comm_groups_no_fabric_is_empty PASSED                                       [ 70%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_comm_groups_intra_node_still_correct PASSED                                 [ 71%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_comm_groups_rdma_still_covers_world PASSED                                  [ 72%]
tests/unittests/test_topology.py::TestNoFabricCluster::test_heap_plan_no_fabric_peers PASSED                                            [ 73%]
tests/unittests/test_topology.py::TestAllFabricCluster::test_comm_groups_fabric_spans_nodes PASSED                                      [ 75%]
tests/unittests/test_topology.py::TestAllFabricCluster::test_comm_groups_no_standalone_groups PASSED                                    [ 76%]
tests/unittests/test_topology.py::TestAllFabricCluster::test_comm_groups_intra_node_still_per_host PASSED                               [ 77%]
tests/unittests/test_topology.py::TestAllFabricCluster::test_heap_plan_fabric_peers_cross_node PASSED                                   [ 78%]
tests/unittests/test_topology.py::TestAllFabricCluster::test_interconnect_cross_node_is_fabric PASSED                                   [ 80%]
tests/unittests/test_topology.py::TestDistributed::test_all_gather_strings SKIPPED (No distributed process group)                       [ 81%]
tests/unittests/test_topology.py::TestDistributed::test_all_gather_strings_empty SKIPPED (No distributed process group)                 [ 82%]
tests/unittests/test_topology.py::TestDistributed::test_all_gather_strings_large_payload SKIPPED (No distributed process group)         [ 83%]
tests/unittests/test_topology.py::TestFullDiscovery::test_discover_returns_topology SKIPPED (No distributed process group)              [ 85%]
tests/unittests/test_topology.py::TestFullDiscovery::test_local_rank_is_unique_per_node SKIPPED (No distributed process group)          [ 86%]
tests/unittests/test_topology.py::TestFullDiscovery::test_own_rank_info_correct SKIPPED (No distributed process group)                  [ 87%]
tests/unittests/test_topology.py::TestFullDiscovery::test_interconnect_symmetry SKIPPED (No distributed process group)                  [ 88%]
tests/unittests/test_topology.py::TestFullDiscovery::test_peer_partition_exhaustive SKIPPED (No distributed process group)              [ 90%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_no_env_var_returns_logical PASSED                                 [ 91%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_nvidia_remapping PASSED                                           [ 92%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_amd_hip_visible PASSED                                            [ 93%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_amd_rocr_fallback PASSED                                          [ 95%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_hip_takes_priority_over_rocr PASSED                               [ 96%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_logical_out_of_range_returns_logical PASSED                       [ 97%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_uuid_style_entry_returns_logical PASSED                           [ 98%]
tests/unittests/test_topology.py::TestLogicalToPhysicalGpuIndex::test_negative_index_passthrough PASSED                                 [100%]

======================================================== 72 passed, 8 skipped in 0.87s ========================================================

Submission Checklist

• Look over the contributing guidelines at https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

This PR improves GPU topology discovery performance by centralizing vendor-library initialization/shutdown into outer scopes, and makes Triton HIP utilities import-safe on non-AMD systems.

Changes:

• Move NVML/AMDSMI lifecycle management out of low-level query helpers and into outer “scope” helpers.
• Add unit tests validating vendor lifecycle behavior and fallbacks when vendor libs are missing.
• Make iris/device_utils.py resilient to missing triton.language.extra.hip symbols.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
tests/unittests/test_topology.py	Adds lifecycle-focused unit tests and fake NVML/AMDSMI modules to validate new behavior.
iris/topology.py	Introduces outer init/shutdown helpers and removes repeated init/shutdown from query helpers to reduce overhead.
iris/device_utils.py	Wraps HIP-only Triton imports and adds compile-time assertions for missing symbols.