diff --git a/src/cudecomp.cc b/src/cudecomp.cc
index fb43822..e67446f 100644
--- a/src/cudecomp.cc
+++ b/src/cudecomp.cc
@@ -86,6 +86,13 @@ static void initNvshmemFromMPIComm(MPI_Comm mpi_comm) {
 }
 #endif
 
+static bool checkEnvVar(const char* env_var_str) {
+  const char* env_var_val_str = std::getenv(env_var_str);
+  bool result = false;
+  if (env_var_val_str) { result = std::strtol(env_var_val_str, nullptr, 10) == 1; }
+  return result;
+}
+
 static void checkTransposeCommBackend(cudecompTransposeCommBackend_t comm_backend) {
   switch (comm_backend) {
   case CUDECOMP_TRANSPOSE_COMM_NCCL:
@@ -199,7 +206,11 @@ static void gatherGlobalMPIInfo(cudecompHandle_t& handle) {
   CHECK_NVML(nvmlDeviceGetHandleByPciBusId(pciBusId, &nvml_dev));
 #if NVML_API_VERSION >= 12 && CUDART_VERSION >= 12040
   nvmlGpuFabricInfoV_t fabricInfo = {.version = nvmlGpuFabricInfo_v2};
-  if (nvmlHasFabricSupport()) {
+
+  // Check CUDECOMP_DISABLE_MNNVL (debug setting to disable MNNVL topology detection)
+  bool disable_mnnvl = checkEnvVar("CUDECOMP_DISABLE_MNNVL");
+
+  if (nvmlHasFabricSupport() && !disable_mnnvl) {
     handle->rank_to_mnnvl_info.resize(handle->nranks);
 
     // Gather MNNVL information (clusterUuid, cliqueId) by rank
@@ -263,12 +274,10 @@ static void gatherGlobalMPIInfo(cudecompHandle_t& handle) {
 
 static void getCudecompEnvVars(cudecompHandle_t& handle) {
   // Check CUDECOMP_ENABLE_NCCL_UBR (NCCL user buffer registration)
-  const char* nccl_enable_ubr_str = std::getenv("CUDECOMP_ENABLE_NCCL_UBR");
-  if (nccl_enable_ubr_str) { handle->nccl_enable_ubr = std::strtol(nccl_enable_ubr_str, nullptr, 10) == 1; }
+  handle->nccl_enable_ubr = checkEnvVar("CUDECOMP_ENABLE_NCCL_UBR");
 
   // Check CUDECOMP_ENABLE_CUMEM (CUDA VMM allocations for work buffers)
-  const char* cumem_enable_str = std::getenv("CUDECOMP_ENABLE_CUMEM");
-  if (cumem_enable_str) { handle->cuda_cumem_enable = std::strtol(cumem_enable_str, nullptr, 10) == 1; }
+  handle->cuda_cumem_enable = checkEnvVar("CUDECOMP_ENABLE_CUMEM");
   if (handle->cuda_cumem_enable) {
 #if CUDART_VERSION < 12030
     if (handle->rank == 0) {
@@ -305,8 +314,7 @@ static void getCudecompEnvVars(cudecompHandle_t& handle) {
   }
 
   // Check CUDECOMP_ENABLE_CUDA_GRAPHS (CUDA Graphs usage in pipelined backends)
-  const char* graphs_enable_str = std::getenv("CUDECOMP_ENABLE_CUDA_GRAPHS");
-  if (graphs_enable_str) { handle->cuda_graphs_enable = std::strtol(graphs_enable_str, nullptr, 10) == 1; }
+  handle->cuda_graphs_enable = checkEnvVar("CUDECOMP_ENABLE_CUDA_GRAPHS");
   if (handle->cuda_graphs_enable) {
 #if CUDART_VERSION < 11010
     if (handle->rank == 0) {
@@ -318,10 +326,7 @@ static void getCudecompEnvVars(cudecompHandle_t& handle) {
   }
 
   // Check CUDECOMP_ENABLE_PERFORMANCE_REPORT (Performance reporting)
-  const char* performance_report_str = std::getenv("CUDECOMP_ENABLE_PERFORMANCE_REPORT");
-  if (performance_report_str) {
-    handle->performance_report_enable = std::strtol(performance_report_str, nullptr, 10) == 1;
-  }
+  handle->performance_report_enable = checkEnvVar("CUDECOMP_ENABLE_PERFORMANCE_REPORT");
 
   // Check CUDECOMP_PERFORMANCE_REPORT_DETAIL (Performance report detail level)
   const char* performance_detail_str = std::getenv("CUDECOMP_PERFORMANCE_REPORT_DETAIL");
@@ -363,8 +368,7 @@ static void getCudecompEnvVars(cudecompHandle_t& handle) {
   if (performance_write_dir_str) { handle->performance_report_write_dir = std::string(performance_write_dir_str); }
 
   // Check CUDECOMP_USE_COL_MAJOR_RANK_ORDER (Column-major rank assignment)
-  const char* col_major_rank_str = std::getenv("CUDECOMP_USE_COL_MAJOR_RANK_ORDER");
-  if (col_major_rank_str) { handle->use_col_major_rank_order = std::strtol(col_major_rank_str, nullptr, 10) == 1; }
+  handle->use_col_major_rank_order = checkEnvVar("CUDECOMP_USE_COL_MAJOR_RANK_ORDER");
 }
 
 #ifdef ENABLE_NVSHMEM
@@ -439,12 +443,12 @@ cudecompResult_t cudecompInit(cudecompHandle_t* handle_in, MPI_Comm mpi_comm) {
     CHECK_CUTENSOR(cutensorInit(&handle->cutensor_handle));
 #endif
 
-    // Gather extra MPI info from all communicator ranks
-    gatherGlobalMPIInfo(handle);
-
     // Gather cuDecomp environment variable settings
     getCudecompEnvVars(handle);
 
+    // Gather extra MPI info from all communicator ranks
+    gatherGlobalMPIInfo(handle);
+
     // Determine P2P CE count
     int dev;
     CUdevice cu_dev;