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tests/python/disco/test_nvshmem.py

@@ -125,6 +125,10 @@ def test_nvshmem_empty(num_workers):
 
 
 if __name__ == "__main__":
+    # After the first call to `nvshmem_init``, a subsequent call to `nvshmem_init`
+    # or `nvshmem_init_thread` in the same program results in undefined behavior.
+    # So we always create a new process to run the test. Then no repeated nvshmem
+    # init happens in the same process, since the worker0 may share the same process.
     for num_worker in [2, 4]:
         for test_func in [test_nvshmem_init, test_nvshmem_empty]:
             p = Process(target=test_func, args=[num_worker])