Merge commit '3d4813d99196bb349eccd50a925e2addc8f1622c' into develop

2026-01-21 20:28:14 +00:00
@@ -0,0 +1,49 @@
+# Compiled shared objects and binaries
+*.so
+*.o
+*.a
+*.out
+*.exe
+*.dll
+*.dylib
+*.bin
+*.elf
+
+# Python cache
+__pycache__/
+*.pyc
+*.pyo
+
+# Build and test artifacts
+/build/
+*.log
+*.tmp
+*.swp
+
+# Ignore all CSV files except scripts/sample_performance_data.csv
+*.csv
+!scripts/sample_performance_data.csv
+
+# Ignore all .conf files except nccl_tuner.conf
+*.conf
+!nccl_tuner.conf
+
+my_configs
+
+# Ignore test binary
+test/test_plugin
+
+# Editor/OS files
+.DS_Store
+Thumbs.db
+
+# Backup files
+*~
+*.bak
+
+# Ignore by convention
+*.old
+*.orig
+
+# Git
+.git/
@@ -0,0 +1,26 @@
+# Find all C source files in current directory
+set(SRC_FILES
+    ${CMAKE_CURRENT_SOURCE_DIR}/plugin.c
+)
+
+# Create shared library
+add_library(nccl-tuner-example SHARED ${SRC_FILES})
+
+# Set include directories
+target_include_directories(nccl-tuner-example PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}/nccl
+)
+
+# Set output name to match Makefile
+set_target_properties(nccl-tuner-example PROPERTIES
+    OUTPUT_NAME "nccl-tuner-example"
+    PREFIX "lib"
+    POSITION_INDEPENDENT_CODE ON
+    LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/test/unit/plugins
+)
+
+# Add custom target for clean (equivalent to Makefile clean target)
+add_custom_target(clean-tuner-lib
+    COMMAND ${CMAKE_COMMAND} -E remove -f ${CMAKE_CURRENT_BINARY_DIR}/libnccl-tuner-example.so
+    COMMENT "Cleaning libnccl-tuner-example.so"
+)
@@ -45,6 +45,40 @@ typedef enum {

 #define NCCL_ALGO_PROTO_IGNORE -1.0

+#define NCCL_HW_NVLINK 0
+#define NCCL_HW_PCI 1
+#define NCCL_HW_NET 2
+#define NCCL_NUM_HW_LINKS 3
+
+#define NCCL_VOLTA_COMPCAP_IDX 0
+#define NCCL_AMPERE_COMPCAP_IDX 1
+#define NCCL_HOPPER_COMPCAP_IDX 2
+#define NCCL_BLACKWELL_COMPCAP_IDX 3
+#define NCCL_NUM_COMPCAPS 4
+
+#define NCCL_TUNING_SCALE_1NODE 0
+#define NCCL_TUNING_SCALE_2NODES 1
+#define NCCL_TUNING_SCALE_4NODES 2
+#define NCCL_NUM_TUNING_SCALES 3
+
+typedef struct {
+  int nNvlDomains;                    // number of NVLink domains
+  int minRanksPerNvlDomain;           // minimum ranks across all NVLink domains
+  int maxRanksPerNvlDomain;           // maximum ranks across all NVLink domains
+} ncclNvlDomainInfo_v5_t;
+
+typedef struct {
+  double baseLatencies [NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
+  double hwLatencies [NCCL_NUM_HW_LINKS][NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
+
+  double llMaxBws [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES];
+  double perChMaxRingLL128Bws [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES];
+  double perChMaxTreeLL128Bws [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES];
+  double perChMaxTreeBws [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES];
+
+
+} ncclTunerConstants_v5_t;
+
 // API to be implemented by external tuner
 typedef struct {
  // Name of the tuner
@@ -52,12 +86,17 @@ typedef struct {

  // Initializes tuner states.
  // Inputs:
+  //   - commId: communicator identifier
  //   - nRanks: number of ranks in current communicator. Each communicator initialize its own tuner.
  //   - nNodes: number of nodes in current communicator.
  //   - logFunction: a logFunction can be useful to integrate logging together with NCCL core.
+  //   - nvlDomainInfo: NVL domain information struct
  // Outputs:
  //   - context: tuner context object
-  ncclResult_t (*init)(size_t nRanks, size_t nNodes, ncclDebugLogger_t logFunction, void **context);
+  // Input/Output:
+  //   - constants: tuner constants
+  ncclResult_t (*init)(void** ctx, uint64_t commId, size_t nRanks, size_t nNodes, ncclDebugLogger_t logFunction,
+                      ncclNvlDomainInfo_v5_t* nvlDomainInfo, ncclTunerConstants_v5_t* constants);

  // Gets info (algo, protocol, number of ctas and threads) for a given collective.
  // Inputs:
@@ -87,11 +126,13 @@ typedef struct {

  // Terminates the plugin and cleans up any resources that the plugin allocated.
  // context: tuner context object
-  ncclResult_t (*destroy)(void* context);
-} ncclTuner_v4_t;
+  ncclResult_t (*finalize)(void* context);
+} ncclTuner_v5_t;

-typedef ncclTuner_v4_t ncclTuner_t;
+typedef ncclTuner_v5_t ncclTuner_t;
+typedef ncclNvlDomainInfo_v5_t ncclNvlDomainInfo_t;
+typedef ncclTunerConstants_v5_t ncclTunerConstants_t;

-#define NCCL_TUNER_PLUGIN_SYMBOL "ncclTunerPlugin_v4"
+#define NCCL_TUNER_PLUGIN_SYMBOL "ncclTunerPlugin_v5"

 #endif
@@ -51,6 +51,7 @@ typedef struct {
  size_t nRanks;
  size_t nNodes;
  ncclDebugLogger_t logFunction;
+  ncclNvlDomainInfo_v5_t nvlDomainInfo;
 } TunerContext;

 // Parse collective type from string
@@ -289,7 +290,25 @@ static ncclResult_t loadConfig(TunerContext* ctx, const char* filename) {
  return ncclSuccess;
 }

-__hidden ncclResult_t pluginInit(size_t nRanks, size_t nNodes, ncclDebugLogger_t logFunction, void **context) {
+__hidden ncclResult_t pluginInit(void** context, uint64_t commId, size_t nRanks, size_t nNodes, ncclDebugLogger_t logFunction,
+                                 ncclNvlDomainInfo_v5_t* nvlDomainInfo, ncclTunerConstants_v5_t* constants) {
+
+  if (NULL != constants) {
+    // NCCL constants tuning
+    // Tune NCCL's internal tuning model to improve base algo/proto selection.
+    // Note: Example numbers are for reference only.
+    //       Actual numbers may vary depending on the hardware and network topology.
+    //       These numbers are not guaranteed to be optimal for all cases.
+    // Limit the tree bandwidth to 15GB/s
+    constants->perChMaxTreeBws[NCCL_BLACKWELL_COMPCAP_IDX][NCCL_TUNING_SCALE_4NODES] = 15.0;
+
+    // Limit the ring bandwidth to 20GB/s
+    constants->perChMaxRingLL128Bws[NCCL_BLACKWELL_COMPCAP_IDX][NCCL_TUNING_SCALE_4NODES] = 20.0;
+
+    // Set NVLSTree base network latency to 24us
+    constants->hwLatencies[NCCL_HW_NET][NCCL_ALGO_NVLS][NCCL_PROTO_SIMPLE] = 24.0;
+  }
+  
  TunerContext* ctx = (TunerContext*)malloc(sizeof(TunerContext));
  if (!ctx) return ncclSystemError;

@@ -299,10 +318,16 @@ __hidden ncclResult_t pluginInit(size_t nRanks, size_t nNodes, ncclDebugLogger_t
  ctx->nRanks = nRanks;
  ctx->nNodes = nNodes;
  ctx->logFunction = logFunction;
+  if (nvlDomainInfo) {
+    ctx->nvlDomainInfo = *nvlDomainInfo;
+  } else {
+    memset(&ctx->nvlDomainInfo, 0, sizeof(ncclNvlDomainInfo_v5_t));
+  }

  if (logFunction) {
    logFunction(NCCL_LOG_INFO, NCCL_TUNING, __FILE__, __LINE__,
-                "TUNER/ExamplePlugin: Initializing tuner for %zu nodes, %zu ranks", nNodes, nRanks);
+                "TUNER/ExamplePlugin: Initializing tuner for %zu nodes, %zu ranks, %d NVL domains",
+                nNodes, nRanks, ctx->nvlDomainInfo.nNvlDomains);
  }

  // Try to load config file from environment variable or default location
@@ -435,7 +460,7 @@ __hidden ncclResult_t pluginGetCollInfo(void* context, ncclFunc_t collType, size
  return ncclSuccess;
 }

-__hidden ncclResult_t pluginDestroy(void* context) {
+__hidden ncclResult_t pluginFinalize(void* context) {
  if (context) {
    TunerContext* ctx = (TunerContext*)context;
    if (ctx->configs) {
@@ -446,11 +471,12 @@ __hidden ncclResult_t pluginDestroy(void* context) {
  return ncclSuccess;
 }

+
 #define PLUGIN_NAME "Example"

-const ncclTuner_v4_t ncclTunerPlugin_v4 = {
+const ncclTuner_v5_t ncclTunerPlugin_v5 = {
  .name = PLUGIN_NAME,
  .init = pluginInit,
  .getCollInfo = pluginGetCollInfo,
-  .destroy = pluginDestroy
+  .finalize = pluginFinalize
 };
@@ -0,0 +1,53 @@
+# NCCL Tuner Configuration File (CSV Format)
+# Format: collective_type,min_bytes,max_bytes,algorithm,protocol,channels,nNodes,nRanks,numPipeOps,regBuff
+#
+# Collective types: broadcast, reduce, allgather, reducescatter, allreduce
+# Algorithms: tree, ring, collnet_direct, collnet_chain, nvls, nvls_tree, pat
+# Protocols: ll, ll128, simple
+# Channels: number of channels to use, or -1 to keep default
+# nNodes: number of nodes to match, or -1 for any number of nodes
+# nRanks: number of ranks to match, or -1 for any number of ranks
+# numPipeOps: number of pipeline operations to match, or -1 for any number (optional)
+# regBuff: whether user buffer can be registered (0=no, 1=yes, -1=any) (optional)
+#
+# Note: numPipeOps and regBuff parameters are optional - configurations without them will match any value
+#
+#AR 4PPN
+allreduce,33554432,4294967296,ring,simple,16,2,8,-1,-1
+allreduce,33554432,4294967296,ring,simple,16,4,16,-1,-1
+allreduce,67108864,4294967296,ring,simple,16,8,32,-1,-1
+#AR 2PPN
+allreduce,2097152,4294967296,ring,simple,4,2,4,-1,-1
+allreduce,16777216,4294967296,ring,simple,4,4,8,-1,-1
+allreduce,33554432,4294967296,ring,simple,4,8,16,-1,-1
+#AR 1PPN
+allreduce,134217728,4294967296,ring,simple,4,4,4,-1,-1
+allreduce,67108864,4294967296,ring,simple,4,8,8,-1,-1
+
+
+#AG 4PPN
+allgather,8388608,4294967296,ring,simple,16,2,8,-1,-1
+allgather,16777216,4294967296,ring,simple,16,4,16,-1,-1
+allgather,16777216,4294967296,ring,simple,16,8,32,-1,-1
+#AG 2PPN
+allgather,262144,4294967296,ring,simple,4,2,4,-1,-1
+allgather,16777216,4294967296,ring,simple,4,4,8,-1,-1
+allgather,33554432,4294967296,ring,simple,4,8,16,-1,-1
+#AG 1PPN
+allgather,262144,2097152,ring,simple,4,2,2,-1,-1
+allgather,262144,8388608,ring,simple,4,4,4,-1,-1
+allgather,67108864,4294967296,ring,simple,4,8,8,-1,-1
+
+#RS 4PPN
+reducescatter,1048576,4294967296,ring,simple,16,2,8,-1,-1
+reducescatter,1048576,4294967296,ring,simple,16,4,16,-1,-1
+reducescatter,1048576,4294967296,ring,simple,16,8,32,-1,-1
+#RS 2PPN
+reducescatter,262144,33554432,ring,simple,4,2,4,-1,-1
+reducescatter,262144,4294967296,ring,simple,4,4,8,-1,-1
+reducescatter,262144,4294967296,ring,simple,4,8,16,-1,-1
+#RS 1PPN
+reducescatter,131072,262144,ring,simple,4,2,2,-1,-1
+reducescatter,1048576,2097152,ring,simple,4,2,2,-1,-1
+reducescatter,131072,4194304,ring,simple,4,4,4,-1,-1
+reducescatter,262144,8388608,ring,simple,4,8,8,-1,-1
@@ -98,12 +98,12 @@ int test_plugin_init() {
  void* context = NULL;

  // Test successful initialization
-  ncclResult_t result = pluginInit(8, 2, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 8, 2, mock_logger, NULL, NULL);
  TEST_ASSERT(result == ncclSuccess, "Plugin init should succeed");
  TEST_ASSERT(context != NULL, "Context should be allocated");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  TEST_PASS();
 }

@@ -123,11 +123,11 @@ int test_config_parsing_valid() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_valid.conf", 1);

  void* context = NULL;
-  ncclResult_t result = pluginInit(16, 2, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 16, 2, mock_logger, NULL, NULL);
  TEST_ASSERT(result == ncclSuccess, "Plugin init with valid config should succeed");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_valid.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -144,12 +144,12 @@ int test_config_parsing_invalid() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_invalid.conf", 1);

  void* context = NULL;
-  ncclResult_t result = pluginInit(8, 1, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);
  // Should still succeed but with no valid configs loaded
  TEST_ASSERT(result == ncclSuccess, "Plugin init should succeed even with invalid config");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_invalid.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -165,7 +165,7 @@ int test_collective_matching() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_match.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  // Create mock cost table
  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
@@ -209,7 +209,7 @@ int test_collective_matching() {
  TEST_ASSERT(nChannels == 4, "Should set 4 channels");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_match.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -226,7 +226,7 @@ int test_size_matching() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_size.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -280,7 +280,7 @@ int test_size_matching() {
  TEST_ASSERT(nChannels == 8, "Large: Should set 8 channels");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_size.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -298,7 +298,7 @@ int test_topology_matching() {

  // Test with single node setup
  void* context1 = NULL;
-  pluginInit(8, 1, mock_logger, &context1);  // 8 ranks, 1 node
+  pluginInit(&context1, 0, 8, 1, mock_logger, NULL, NULL);  // 8 ranks, 1 node

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -316,11 +316,11 @@ int test_topology_matching() {
  TEST_ASSERT(cost_table[NCCL_ALGO_TREE][NCCL_PROTO_SIMPLE] == 0.0, "Single node: Should match tree config");
  TEST_ASSERT(nChannels == 2, "Single node: Should set 2 channels");

-  pluginDestroy(context1);
+  pluginFinalize(context1);

  // Test with 4 nodes, 32 ranks setup
  void* context2 = NULL;
-  pluginInit(32, 4, mock_logger, &context2);  // 32 ranks, 4 nodes
+  pluginInit(&context2, 0, 32, 4, mock_logger, NULL, NULL);  // 32 ranks, 4 nodes

  for (int i = 0; i < NCCL_NUM_ALGORITHMS; i++) {
    for (int j = 0; j < NCCL_NUM_PROTOCOLS; j++) {
@@ -349,7 +349,7 @@ int test_default_channels() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_default.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -369,7 +369,7 @@ int test_default_channels() {
  TEST_ASSERT(nChannels == 1, "Should keep default channels (1) when config has -1");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_default.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -386,7 +386,7 @@ int test_regbuff_matching() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_regbuff.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -437,7 +437,7 @@ int test_regbuff_matching() {
  TEST_ASSERT(nChannels == 8, "Any regBuff: Should set 8 channels");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_regbuff.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -454,7 +454,7 @@ int test_pipeops_matching() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_pipeops.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -504,7 +504,7 @@ int test_pipeops_matching() {
  TEST_ASSERT(nChannels == 8, "Any pipeOps: Should set 8 channels");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_pipeops.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -519,7 +519,7 @@ int test_no_match_fallback() {
  setenv("NCCL_TUNER_CONFIG_FILE", "test_fallback.conf", 1);

  void* context = NULL;
-  pluginInit(8, 1, mock_logger, &context);
+  pluginInit(&context, 0, 8, 1, mock_logger, NULL, NULL);

  float cost_table[NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS];
  float* cost_table_ptr[NCCL_NUM_ALGORITHMS];
@@ -543,7 +543,7 @@ int test_no_match_fallback() {
  TEST_ASSERT(nChannels == 1, "Should use default channels");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink("test_fallback.conf");
  unsetenv("NCCL_TUNER_CONFIG_FILE");
  TEST_PASS();
@@ -593,7 +593,7 @@ int test_large_config() {

  // Initialize plugin with large config
  void* context = NULL;
-  ncclResult_t result = pluginInit(16, 4, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 16, 4, mock_logger, NULL, NULL);
  TEST_ASSERT(result == ncclSuccess, "Plugin init with large config should succeed");
  TEST_ASSERT(context != NULL, "Context should be allocated");

@@ -652,7 +652,7 @@ int test_large_config() {
  TEST_ASSERT(result == ncclSuccess, "GetCollInfo should work with large config set");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink(large_config_file);
  unsetenv("NCCL_TUNER_CONFIG_FILE");

@@ -684,7 +684,7 @@ int test_very_large_config_stress() {

  // Test initialization with stress config
  void* context = NULL;
-  ncclResult_t result = pluginInit(8, 2, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 8, 2, mock_logger, NULL, NULL);
  TEST_ASSERT(result == ncclSuccess, "Plugin should handle very large config files");

  TunerContext* ctx = (TunerContext*)context;
@@ -705,7 +705,7 @@ int test_very_large_config_stress() {
  }

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink(stress_config_file);
  unsetenv("NCCL_TUNER_CONFIG_FILE");

@@ -726,7 +726,7 @@ int test_empty_config() {
  setenv("NCCL_TUNER_CONFIG_FILE", empty_config_file, 1);

  void* context = NULL;
-  ncclResult_t result = pluginInit(8, 2, mock_logger, &context);
+  ncclResult_t result = pluginInit(&context, 0, 8, 2, mock_logger, NULL, NULL);
  TEST_ASSERT(result == ncclSuccess, "Plugin should handle empty config files");

  TunerContext* ctx = (TunerContext*)context;
@@ -751,13 +751,134 @@ int test_empty_config() {
  TEST_ASSERT(result == ncclSuccess, "GetCollInfo should work with empty config");

  // Clean up
-  pluginDestroy(context);
+  pluginFinalize(context);
  unlink(empty_config_file);
  unsetenv("NCCL_TUNER_CONFIG_FILE");

  TEST_PASS();
 }

+// Test NVLink domain info handling
+int test_nvl_domain_info() {
+  printf("Testing NVLink domain info handling...\n");
+
+  // Test NVLink domain structure with min/max ranks per domain
+  ncclNvlDomainInfo_v5_t nvl_domain = {
+    .nNvlDomains = 2, // 2 nodes = 2 domains
+    .minRanksPerNvlDomain = 3, // minimum ranks across all domains (bottleneck)
+    .maxRanksPerNvlDomain = 5  // maximum ranks across all domains (capacity)
+  };
+  
+  void* context = NULL;
+  ncclResult_t result = pluginInit(&context, 0, 8, 2, mock_logger, &nvl_domain, NULL);
+  TEST_ASSERT(result == ncclSuccess, "Plugin init with NVLink domains should succeed");
+  
+  // Validate NVLD info structure
+  TEST_ASSERT(nvl_domain.nNvlDomains == 2, "Should have 2 domains (nodes)");
+  TEST_ASSERT(nvl_domain.minRanksPerNvlDomain == 3, "Should have minimum 3 ranks per domain");
+  TEST_ASSERT(nvl_domain.maxRanksPerNvlDomain == 5, "Should have maximum 5 ranks per domain");
+  
+  // Clean up
+  pluginFinalize(context);
+  printf("NVLink domain info test passed!\n");
+  TEST_PASS();
+}
+
+int test_tuner_constants() {
+  // Initialize constants to -1.0 for testing purposes
+  ncclTunerConstants_v5_t constants = {
+    // Base latencies: [NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS]
+    .baseLatencies = {
+      {-1.0, -1.0, -1.0},    // NCCL_ALGO_TREE: LL, LL128, Simple
+      {-1.0, -1.0, -1.0},    // NCCL_ALGO_RING: LL, LL128, Simple
+      {-1.0, -1.0, -1.0},   // NCCL_ALGO_COLLNET_DIRECT
+      {-1.0, -1.0, -1.0},   // NCCL_ALGO_COLLNET_CHAIN
+      {-1.0, -1.0, -1.0},    // NCCL_ALGO_NVLS
+      {-1.0, -1.0, -1.0},    // NCCL_ALGO_NVLS_TREE
+      {-1.0, -1.0, -1.0}     // NCCL_ALGO_PAT
+    },
+
+    // Hardware latencies: [NCCL_NUM_HW_LINKS][NCCL_NUM_ALGORITHMS][NCCL_NUM_PROTOCOLS]
+    .hwLatencies = {
+      // NCCL_HW_NVLINK
+      {
+        {-1.0, -1.0, -1.0},    // TREE
+        {-1.0, -1.0, -1.0},    // RING
+        {-1.0, -1.0, -1.0},    // COLLNET_DIRECT
+        {-1.0, -1.0, -1.0},    // COLLNET_CHAIN
+        {-1.0, -1.0, -1.0},    // NVLS
+        {-1.0, -1.0, -1.0},    // NVLS_TREE
+        {-1.0, -1.0, -1.0}     // PAT
+      },
+      // NCCL_HW_PCI
+      {
+        {-1.0, -1.0, -1.0},   // TREE
+        {-1.0, -1.0, -1.0},    // RING
+        {-1.0, -1.0, -1.0},  // COLLNET_DIRECT
+        {-1.0, -1.0, -1.0},  // COLLNET_CHAIN
+        {-1.0, -1.0, -1.0},     // NVLS
+        {-1.0, -1.0, -1.0},   // NVLS_TREE
+        {-1.0, -1.0, -1.0}   // PAT
+      },
+      // NCCL_HW_NET
+      {
+        {-1.0, -1.0, -1.0},  // TREE
+        {-1.0, -1.0, -1.0},  // RING
+        {-1.0, -1.0, -1.0},  // COLLNET_DIRECT
+        {-1.0, -1.0, -1.0},  // COLLNET_CHAIN
+        {-1.0, -1.0, -1.0},  // NVLS
+        {-1.0, -1.0, -1.0},  // NVLS_TREE
+        {-1.0, -1.0, -1.0}   // PAT
+      }
+    },
+
+    // LL maximum bandwidths: [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES]
+    .llMaxBws = {
+      {-1.0, -1.0, -1.0},  // Volta: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Ampere: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Hopper: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0}   // Blackwell: 1node, 2nodes, 4nodes
+    },
+
+    // Per-channel maximum Ring LL128 bandwidths: [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES]
+    .perChMaxRingLL128Bws = {
+      {-1.0, -1.0, -1.0},   // Volta: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Ampere: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Hopper: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0}   // Blackwell: 1node, 2nodes, 4nodes
+    },
+
+    // Per-channel maximum Tree LL128 bandwidths: [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES]
+    .perChMaxTreeLL128Bws = {
+      {-1.0, -1.0, -1.0},    // Volta: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},   // Ampere: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Hopper: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0}   // Blackwell: 1node, 2nodes, 4nodes
+    },
+
+    // Per-channel maximum Tree bandwidths: [NCCL_NUM_COMPCAPS][NCCL_NUM_TUNING_SCALES]
+    .perChMaxTreeBws = {
+      {-1.0, -1.0, -1.0},  // Volta: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Ampere: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0},  // Hopper: 1node, 2nodes, 4nodes
+      {-1.0, -1.0, -1.0}   // Blackwell: 1node, 2nodes, 4nodes
+    }
+  };
+
+  void* context = NULL;
+  ncclResult_t result = pluginInit(&context, 0, 8, 2, mock_logger, NULL, &constants);
+  TEST_ASSERT(result == ncclSuccess, "Plugin init with constants should succeed");
+
+  // Test that the constants were set correctly
+  TEST_ASSERT(constants.perChMaxTreeBws[NCCL_BLACKWELL_COMPCAP_IDX][NCCL_TUNING_SCALE_4NODES] == 15.0, "Tree bandwidth should be 15GB/s");
+  TEST_ASSERT(constants.perChMaxRingLL128Bws[NCCL_BLACKWELL_COMPCAP_IDX][NCCL_TUNING_SCALE_4NODES] == 20.0, "Ring bandwidth should be 20GB/s");
+  TEST_ASSERT(constants.hwLatencies[NCCL_HW_NET][NCCL_ALGO_NVLS][NCCL_PROTO_SIMPLE] == 24.0, "NVLSTree base network latency should be 24us");
+
+  // Clean up
+  pluginFinalize(context);
+  TEST_PASS();
+}
+
 // Test runner function pointer type
 typedef int (*TestFunction)(void);

@@ -783,6 +904,8 @@ TestCase test_cases[] = {
  {"large-config", test_large_config, "Large configuration files (dynamic allocation)"},
  {"stress-config", test_very_large_config_stress, "Very large configuration stress test"},
  {"empty-config", test_empty_config, "Empty configuration file handling"},
+  {"nvl-domain", test_nvl_domain_info, "NVL domain info handling"},
+  {"constants", test_tuner_constants, "Tuner constants initialization"},
  {NULL, NULL, NULL} // End marker
 };

@@ -826,6 +949,7 @@ int main(int argc, char* argv[]) {
  if (argc == 1) {
    // No arguments - run all tests
    for (int i = 0; test_cases[i].name != NULL; i++) {
+      printf("Running test: %s\n", test_cases[i].name);
      total++;
      passed += test_cases[i].func();
    }