2.9.6-1

Add support for CUDA graphs.
Fuse BCM Gen4 switches to avoid suboptimal performance on some platforms. Issue #439.
Fix bootstrap issue caused by connection reordering.
Fix CPU locking block.
Improve CollNet algorithm.
Improve performance on DGX A100 for communicators with only one GPU per node.

src/include/devcomm.h

@@ -1,5 +1,5 @@
 /*************************************************************************
- * Copyright (c) 2015-2020, NVIDIA CORPORATION. All rights reserved.
+ * Copyright (c) 2015-2021, NVIDIA CORPORATION. All rights reserved.
  *
  * See LICENSE.txt for license information
  ************************************************************************/
@@ -99,8 +99,9 @@ struct ncclConnInfo {
 struct ncclConnector {
   int connected;
   struct ncclProxyArgs *proxyAppend;
+  struct ncclProxyArgs **proxyAppendPtr;
   struct ncclTransportComm* transportComm;
-  void* transportResources; // Host-side resources
+  void* transportResources;
   struct ncclConnInfo conn;
   struct ncclComm *comm;
 };
@@ -125,9 +126,21 @@ struct ncclTree {
   int down[NCCL_MAX_TREE_ARITY];
 };
 
+#define NCCL_MAX_DIRECT_ARITY 7
+struct ncclDirect {
+  int depth;
+  int out;
+  int nHeads;
+  int headRank;
+  int shift;
+  int up[NCCL_MAX_DIRECT_ARITY];
+  int down[NCCL_MAX_DIRECT_ARITY];
+};
+
+#define NCCL_MAX_CONNS 2
 struct ncclPeer {
-  struct ncclConnector send;
-  struct ncclConnector recv;
+  struct ncclConnector send[NCCL_MAX_CONNS];
+  struct ncclConnector recv[NCCL_MAX_CONNS];
 };
 
 struct ncclDevComm;
@@ -161,6 +174,8 @@ struct ncclWorkElem {
     struct {
       size_t sendCount;
       size_t recvCount;
+      int sendChunkSize;
+      int recvChunkSize;
       int32_t delta;
       uint16_t nThreads;
     } p2p;
@@ -177,7 +192,7 @@ struct ncclChannel {
     struct {
       struct ncclRing ring;
       struct ncclTree tree;
-      struct ncclTree collTree;
+      struct ncclDirect collTree;
 
       int id;
 
@@ -189,6 +204,12 @@ struct ncclChannel {
       struct ncclWork* workFifo;
       int workCount;
       uint64_t workFifoTail; // Only used by CPU
+      uint16_t index;        // Only used by GPU
+
+      // GDRCOPY support
+      struct ncclWork* workFifoGdr;
+      struct ncclWork* workFifoDev;
+      void* gdrMemDesc;
     };
     int data[0x80];
   };