2.22.3-1

Rework core for NVIDIA Trusted Computing
 * Compress work structs so that they are shared between channels
 * Utilize the full amount of kernel argument space permitted (4k)
   before resorting to work fifo.
 * Rework the task preprocessing phase.
 * Use a separate abortDevFlag which is kept in sync with abortFlag
   using cudaMemcpy operations.
 * Rename src/include/align.h to src/include/bitops.h

Add lazy connection establishment for collective operations
 * Move buffer allocation and connection establishment to the first
   collective operation using that algorithm.
 * Accelerate init time and reduce memory usage.
 * Avoid allocating NVLS buffers if all calls are registered.
 * Compute algo/proto in ncclLaunchCollTasksInfo early on.
 * Connect peers in ncclCollPreconnectFunc if not connected already.
 * Also move shared buffer creation to the first send/recv call.

Accelerate intra-node NVLink detection
 * Make each rank only detect NVLinks attached to its GPU.
 * Fuse XMLs to reconstruct the full NVLink topology

Add init profiling to report time spend in different init phases.
 * Report timings of bootstrap, allgather, search, connect, etc.
 * Add new "PROFILE" category for NCCL_DEBUG_SUBSYS.

Add support for PCI p2p on split PCI switches
 * Detect split PCI switches through a kernel module exposing
   switch information.
 * Update the topology XML and graph to add those inter-switch
   connections.

Add cost estimation API
 * Add a new ncclGroupEndSimulate primitive to return the estimated
   time a group would take.

Net/IB: Add separate traffic class for fifo messages
 * Add NCCL_IB_FIFO_TC to control the traffic class of fifo messages
   independently from NCCL_IB_TC.
   Merges PR #1194

Net/IB: Add support for IB router
 * Use flid instead of lid if subnets do not match
 * Warn if flid is 0

Optimizations and fixes for device network offload (unpack)
 * Double the default number of channels
 * Cache netDeviceType
 * Fix save/increment head logic to enable Tree support.

Support ncclGroupStart/End for ncclCommAbort/Destroy
 * Allow Abort/Destroy to be called within a group when managing
   multiple GPUs with a single process.

Improve Tuner API
 * Provide to the plugin the original cost table so that the plugin
   can leave unknown or disabled algo/proto combinations untouched.
 * Remove nvlsSupport and collnetSupport.

Do not print version to stdout when using a debug file
 * Also print version from all processes with INFO debug level.
   Fixes issue #1271

Fix clang warnings in NVTX headers
 * Update NVTX headers to the latest version
   Fixes issue #1270

Disable port fusion in heterogeneous systems
 * Do not fuse ports if a mix of multi-port and single port are detected.

Fix NVLS graphs search for dual NICs.
 * Fix NVLS graph search when we have more than one NIC per GPU.

Fix crash with collnetDirect
 * Add separate graph search for collnetDirect, testing alltoall paths
   and working similarly to the NVLS search.

Fix hang when nodes have different CPU types
 * Add the CPU type to the rank peer info.
 * Align all ranks on the CPU type after the first allgather.
 * Only use the aligned CPU type for all tuning operations.
   Fixes issue #1136
   Fixes issue #1184

Fix performance of registered send/recv operations
 * Allow for single full size operations
 * Add INFO to confirm the registration of send/recv buffers.

Move all sync ops to finalize stage
 * Ensure ncclCommDestroy is non-blocking if ncclCommFinalize has
   been called.

Improve error reporting during SHM segment creation

Improve support of various compilers
   Merges PR #1177
   Merges PR #1228

Allow net and tuner plugins to be statically linked
 * Search for ncclNet or ncclTuner symbols in the main binary.
   Merges PR #979

Plugin examples includes cleanup
 * Harmonize err.h and common.h usage.
 * Add mixed plugin with both net and tuner.

Author: sjeaugey

ext-net/example/nccl/common.h

@@ -0,0 +1,15 @@
+/*************************************************************************
+ * Copyright (c) 2024, NVIDIA CORPORATION. All rights reserved.
+ *
+ * See LICENSE.txt for license information
+ ************************************************************************/
+
+#ifndef COMMON_H_
+#define COMMON_H_
+
+typedef enum {NCCL_LOG_NONE=0, NCCL_LOG_VERSION=1, NCCL_LOG_WARN=2, NCCL_LOG_INFO=3, NCCL_LOG_ABORT=4, NCCL_LOG_TRACE=5} ncclDebugLogLevel;
+typedef enum {NCCL_INIT=1, NCCL_COLL=2, NCCL_P2P=4, NCCL_SHM=8, NCCL_NET=16, NCCL_GRAPH=32, NCCL_TUNING=64, NCCL_ENV=128, NCCL_ALLOC=256, NCCL_CALL=512, NCCL_PROXY=1024, NCCL_NVLS=2048, NCCL_BOOTSTRAP=4096, NCCL_REG=8192, NCCL_ALL=~0} ncclDebugLogSubSys;
+
+typedef void (*ncclDebugLogger_t)(ncclDebugLogLevel level, unsigned long flags, const char *file, int line, const char *fmt, ...);
+
+#endif

ext-net/example/nccl/err.h

@@ -11,6 +11,7 @@ typedef enum { ncclSuccess                 =  0,
                ncclSystemError             =  2,
                ncclInternalError           =  3,
                ncclInvalidArgument         =  4,
+               ncclInvalidUsage            =  5,
                ncclRemoteError             =  6 } ncclResult_t;
 
 #endif

ext-net/example/nccl/net.h

@@ -8,6 +8,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+#include "common.h"
 #include "err.h"
 
 #define NCCL_NET_HANDLE_MAXSIZE 128
@@ -19,11 +20,6 @@
 // Maximum number of requests per comm object
 #define NCCL_NET_MAX_REQUESTS 32
 
-typedef enum {NCCL_LOG_NONE=0, NCCL_LOG_VERSION=1, NCCL_LOG_WARN=2, NCCL_LOG_INFO=3, NCCL_LOG_ABORT=4, NCCL_LOG_TRACE=5} ncclDebugLogLevel;
-typedef enum {NCCL_INIT=1, NCCL_COLL=2, NCCL_P2P=4, NCCL_SHM=8, NCCL_NET=16, NCCL_GRAPH=32, NCCL_TUNING=64, NCCL_ENV=128, NCCL_ALLOC=256, NCCL_CALL=512, NCCL_ALL=~0} ncclDebugLogSubSys;
-
-typedef void (*ncclDebugLogger_t)(ncclDebugLogLevel level, unsigned long flags, const char *file, int line, const char *fmt, ...);
-
 #include "net_v8.h"
 #include "net_v7.h"
 #include "net_v6.h"

ext-net/example/nccl/types.h

@@ -2,8 +2,8 @@
  * Copyright (c) 2017-2022, NVIDIA CORPORATION. All rights reserved.
  */
 
-#ifndef NCCL_ERR_H_
-#define NCCL_ERR_H_
+#ifndef NCCL_TYPES_H_
+#define NCCL_TYPES_H_
 
 /* Data types */
 typedef enum { ncclInt8       = 0, ncclChar       = 0,

ext-tuner/example/nccl/common.h

@@ -0,0 +1,15 @@
+/*************************************************************************
+ * Copyright (c) 2024, NVIDIA CORPORATION. All rights reserved.
+ *
+ * See LICENSE.txt for license information
+ ************************************************************************/
+
+#ifndef COMMON_H_
+#define COMMON_H_
+
+typedef enum {NCCL_LOG_NONE=0, NCCL_LOG_VERSION=1, NCCL_LOG_WARN=2, NCCL_LOG_INFO=3, NCCL_LOG_ABORT=4, NCCL_LOG_TRACE=5} ncclDebugLogLevel;
+typedef enum {NCCL_INIT=1, NCCL_COLL=2, NCCL_P2P=4, NCCL_SHM=8, NCCL_NET=16, NCCL_GRAPH=32, NCCL_TUNING=64, NCCL_ENV=128, NCCL_ALLOC=256, NCCL_CALL=512, NCCL_PROXY=1024, NCCL_NVLS=2048, NCCL_BOOTSTRAP=4096, NCCL_REG=8192, NCCL_ALL=~0} ncclDebugLogSubSys;
+
+typedef void (*ncclDebugLogger_t)(ncclDebugLogLevel level, unsigned long flags, const char *file, int line, const char *fmt, ...);
+
+#endif

ext-tuner/example/nccl/err.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2017-2022, NVIDIA CORPORATION. All rights reserved.
+ */
+
+#ifndef NCCL_ERR_H_
+#define NCCL_ERR_H_
+
+/* Error type for plugins */
+typedef enum { ncclSuccess                 =  0,
+               ncclUnhandledCudaError      =  1,
+               ncclSystemError             =  2,
+               ncclInternalError           =  3,
+               ncclInvalidArgument         =  4,
+               ncclInvalidUsage            =  5,
+               ncclRemoteError             =  6 } ncclResult_t;
+
+#endif

ext-tuner/example/nccl/tuner.h

@@ -8,15 +8,24 @@
 #ifndef NCCL_TUNER_H_
 #define NCCL_TUNER_H_
 
-#include "nccl.h"
+#include <stdint.h>
+#include <stdlib.h>
 
-typedef enum {NCCL_LOG_NONE=0, NCCL_LOG_VERSION=1, NCCL_LOG_WARN=2, NCCL_LOG_INFO=3, NCCL_LOG_ABORT=4, NCCL_LOG_TRACE=5} ncclDebugLogLevel;
-typedef enum {NCCL_INIT=1, NCCL_COLL=2, NCCL_P2P=4, NCCL_SHM=8, NCCL_NET=16, NCCL_GRAPH=32, NCCL_TUNING=64, NCCL_ENV=128, NCCL_ALLOC=256, NCCL_CALL=512, NCCL_PROXY=1024, NCCL_NVLS=2048, NCCL_ALL=~0} ncclDebugLogSubSys;
-
-typedef void (*ncclDebugLogger_t)(ncclDebugLogLevel level, unsigned long flags, const char *file, int line, const char *fmt, ...);
+#include "common.h"
+#include "err.h"
 
 #define NCCL_NUM_FUNCTIONS 5 // Send/Recv not included for now
-typedef enum { ncclFuncBroadcast, ncclFuncReduce, ncclFuncAllGather, ncclFuncReduceScatter, ncclFuncAllReduce, ncclFuncSendRecv, ncclFuncSend, ncclFuncRecv, ncclNumFuncs} ncclFunc_t;
+typedef enum {
+  ncclFuncBroadcast = 0,
+  ncclFuncReduce = 1,
+  ncclFuncAllGather = 2,
+  ncclFuncReduceScatter = 3,
+  ncclFuncAllReduce = 4,
+  ncclFuncSendRecv = 5,
+  ncclFuncSend = 6,
+  ncclFuncRecv = 7,
+  ncclNumFuncs = 8
+} ncclFunc_t;
 
 #define NCCL_NUM_ALGORITHMS 6 // Tree/Ring/CollNet*
 #define NCCL_ALGO_UNDEF -1
@@ -33,6 +42,8 @@ typedef enum { ncclFuncBroadcast, ncclFuncReduce, ncclFuncAllGather, ncclFuncRed
 #define NCCL_PROTO_LL128 1
 #define NCCL_PROTO_SIMPLE 2
 
+#define NCCL_ALGO_PROTO_IGNORE -1.0
+
 // API to be implemented by external tuner
 typedef struct {
   // Name of the tuner
@@ -52,31 +63,33 @@ typedef struct {
   //   - context: tuner context object
   //   - collType: collective type , e.g., allreduce, allgather…
   //   - nBytes: collective size in bytes
-  //   - collNetSupport: whether collnet supports this type
-  //   - nvlsSupport: whether nvlink sharp supports this time
   //   - numPipeOps: number of operations in the group
+  //   - numAlgo: number of algorithms in collCostTable
+  //   - numProto: number of protocols in collCostTable
   //
   // Outputs:
-  //   - algorithm: selected algorithm to be used for the given collective
-  //   - protocol: selected protocol to be used for the given collective
   //   - nChannels: number of channels (hence SMs) to be used.
   //
+  // InOut:
+  //   - collCostTable: collective cost table, generated by NCCL core, containing algo|proto|time entries for collType.
+  //                    NCCL core sets ignored algo/proto cost table entries to -1.0 (NCCL_ALGO_PROTO_IGNORE).
+  //
   // If getCollInfo() does not return ncclSuccess, NCCL will fall back to the
   // default tuning for the given collective.
   // Also, the plugin is allowed to not set any output, or set only the
   // algorithm and protocol, but not only the algorithm or only the protocol.
   // Unset fields will be set automatically by NCCL.
   ncclResult_t (*getCollInfo)(void* context, ncclFunc_t collType, size_t nBytes,
-                              int collNetSupport, int nvlsSupport, int numPipeOps,
-                              int *algorithm, int *protocol, int* nChannels);
+                              int numPipeOps, float** collCostTable, int numAlgo, int numProto,
+                              int* nChannels);
 
   // Terminates the plugin and cleans up any resources that the plugin allocated.
   // context: tuner context object
   ncclResult_t (*destroy)(void* context);
-} ncclTuner_v2_t;
+} ncclTuner_v3_t;
 
-typedef ncclTuner_v2_t ncclTuner_t;
+typedef ncclTuner_v3_t ncclTuner_t;
 
-#define NCCL_TUNER_PLUGIN_SYMBOL "ncclTunerPlugin_v2"
+#define NCCL_TUNER_PLUGIN_SYMBOL "ncclTunerPlugin_v3"
 
 #endif

ext-tuner/example/plugin.c

@@ -11,14 +11,21 @@
 __hidden ncclResult_t pluginInit(size_t nRanks, size_t nNodes, ncclDebugLogger_t logFunction, void **context) { return ncclSuccess; }
 
 __hidden ncclResult_t pluginGetCollInfo(void* context, ncclFunc_t collType, size_t nBytes,
-                              int collNetSupport, int nvlsSupport, int numPipeOps,
-                              int *algorithm, int *protocol, int* nChannels) { *algorithm = NCCL_ALGO_RING; *protocol = NCCL_PROTO_SIMPLE; return ncclSuccess; }
+                              int numPipeOps, float** collCostTable, int numAlgo, int numProto,
+                              int* nChannels) {
+  // Update NCCL core generated cost table. Updated table will be evaluated by NCCL to pick the best algo/proto combo
+  if (collCostTable[NCCL_ALGO_RING][NCCL_PROTO_SIMPLE] != NCCL_ALGO_PROTO_IGNORE) {
+    collCostTable[NCCL_ALGO_RING][NCCL_PROTO_SIMPLE] = 0.0;
+  }
+  *nChannels = 1;
+  return ncclSuccess;
+}
 
 __hidden ncclResult_t pluginDestroy(void* context) { return ncclSuccess; }
 
 #define PLUGIN_NAME "Example"
 
-const ncclTuner_v2_t ncclTunerPlugin_v2 = {
+const ncclTuner_v3_t ncclTunerPlugin_v3 = {
   .name = PLUGIN_NAME,
   .init = pluginInit,
   .getCollInfo = pluginGetCollInfo,

makefiles/version.mk

@@ -1,6 +1,6 @@
 ##### version
 NCCL_MAJOR   := 2
-NCCL_MINOR   := 21
-NCCL_PATCH   := 5
+NCCL_MINOR   := 22
+NCCL_PATCH   := 3
 NCCL_SUFFIX  :=
 PKG_REVISION := 1

src/bootstrap.cc

@@ -201,7 +201,6 @@ ncclResult_t bootstrapCreateRoot(struct ncclBootstrapHandle* handle, bool idFrom
 
 ncclResult_t bootstrapGetUniqueId(struct ncclBootstrapHandle* handle) {
   memset(handle, 0, sizeof(ncclBootstrapHandle));
-  NCCLCHECK(getRandomData(&handle->magic, sizeof(handle->magic)));
 
   const char* env = ncclGetEnv("NCCL_COMM_ID");
   if (env) {
@@ -210,7 +209,9 @@ ncclResult_t bootstrapGetUniqueId(struct ncclBootstrapHandle* handle) {
       WARN("Invalid NCCL_COMM_ID, please use format: <ipv4>:<port> or [<ipv6>]:<port> or <hostname>:<port>");
       return ncclInvalidArgument;
     }
+    handle->magic = NCCL_MAGIC;
   } else {
+    NCCLCHECK(getRandomData(&handle->magic, sizeof(handle->magic)));
     memcpy(&handle->addr, &bootstrapNetIfAddr, sizeof(union ncclSocketAddress));
     NCCLCHECK(bootstrapCreateRoot(handle, false));
   }
@@ -626,7 +627,7 @@ ncclResult_t bootstrapClose(void* commState) {
   struct bootstrapState* state = (struct bootstrapState*)commState;
   if (state->unexpectedConnections != NULL) {
     unexpectedFree(state);
-    if (__atomic_load_n(state->abortFlag, __ATOMIC_RELAXED) == 0) {
+    if (__atomic_load_n(state->abortFlag, __ATOMIC_ACQUIRE) == 0) {
       WARN("Unexpected connections are not empty");
       return ncclInternalError;
     }