2.3.5-5

Add support for inter-node communication using sockets and InfiniBand/RoCE. Improve latency. Add support for aggregation. Improve LL/regular tuning. Remove tests as those are now at github.com/nvidia/nccl-tests . [ROCm/rccl commit: f93fe9bfd9]
2018-09-24 16:06:59 -07:00
parent 63ab6df5b3
commit 8ffcfac437
132 changed files with 12424 additions and 9415 deletions
@@ -0,0 +1,195 @@
+/*************************************************************************
+ * Copyright (c) 2016-2018, NVIDIA CORPORATION. All rights reserved.
+ *
+ * See LICENSE.txt for license information
+ ************************************************************************/
+
+#ifndef COMMON_COLL_H_
+#define COMMON_COLL_H_
+
+#include "core.h"
+#include "enqueue.h"
+#include "collectives/collectives.h"
+
+static ncclResult_t PointerCheck(const void* pointer, struct ncclComm* comm, const char* ptrname, const char* opname) {
+  cudaPointerAttributes attr;
+  cudaError_t err = cudaPointerGetAttributes(&attr, pointer);
+  if (err != cudaSuccess || attr.devicePointer == NULL) {
+    WARN("%s : %s is not a valid pointer", opname, ptrname);
+    return ncclInvalidArgument;
+  }
+#if __CUDACC_VER_MAJOR__ >= 10
+  if (attr.type == cudaMemoryTypeDevice && attr.device != comm->cudaDev) {
+#else
+  if (attr.memoryType == cudaMemoryTypeDevice && attr.device != comm->cudaDev) {
+#endif
+    WARN("%s : %s allocated on device %d mismatchs with NCCL device %d", opname, ptrname, attr.device, comm->cudaDev);
+    return ncclInvalidArgument;
+  }
+  return ncclSuccess;
+}
+
+static ncclResult_t PtrCheck(void* ptr, const char* opname, const char* ptrname) {
+  if (ptr == NULL) {
+    WARN("%s : %s argument is NULL", opname, ptrname);
+    return ncclInvalidArgument;
+  }
+  return ncclSuccess;
+}
+
+static ncclResult_t ArgsCheck(const void* sendbuff, const void* recvbuff, size_t count, ncclDataType_t type, ncclRedOp_t op, int root, struct ncclComm* comm, const char* opname) {
+  NCCLCHECK(PtrCheck(comm, opname, "comm"));
+  // First, the easy ones
+  if (root < 0 || root >= comm->nRanks) {
+    WARN("%s : invalid root %d (root should be in the 0..%d range)", opname, root, comm->nRanks);
+    return ncclInvalidArgument;
+  }
+  if (type < 0 || type >= ncclNumTypes) {
+    WARN("%s : invalid type %d", opname, type);
+    return ncclInvalidArgument;
+  }
+  if (op < 0 || op >= ncclNumOps) {
+    WARN("%s : invalid reduction operation %d", opname, op);
+    return ncclInvalidArgument;
+  }
+
+  if (comm->checkPointers) {
+    // Check CUDA device pointers
+    if (strcmp(opname, "Broadcast") != 0 || comm->rank == root) {
+      NCCLCHECK(PointerCheck(sendbuff, comm, "sendbuff", opname));
+    }
+    if (strcmp(opname, "Reduce") != 0 || comm->rank == root) {
+      NCCLCHECK(PointerCheck(recvbuff, comm, "recvbuff", opname));
+    }
+  }
+  return ncclSuccess;
+}
+
+static __inline__ int ncclTypeSize(ncclDataType_t type) {
+  switch (type) {
+    case ncclInt8:
+    case ncclUint8:
+      return 1;
+    case ncclFloat16:
+      return 2;
+    case ncclInt32:
+    case ncclUint32:
+    case ncclFloat32:
+      return 4;
+    case ncclInt64:
+    case ncclUint64:
+    case ncclFloat64:
+      return 8;
+    default:
+      return -1;
+  }
+}
+
+// In : comm, nbytes ; Out : nrings, nthreads, ll
+// - We start with the minimum number of threads possible (64) and see if the size fits in LL;
+//   If not, we increase the number of threads by 2x, until we reach the max number of LL threads (256, or set by user via NCCL_NTHREADS, or platform non-LL default)
+// - We use "maxRings" to limit the max number of rings we can use before reaching the max number of LL threads
+//   This ensures we don't use a large number of rings with a small number of threads
+// - We use the NCCL_LL_RING_THRESHOLD as the per-thread threshold before we reach the max number of threads
+//   we use NCCL_THREAD_THRESHOLD when we reach the max
+// - If by the max number of LL threads, the size still cannot fit in LL, then we use non-LL setting
+// - We honor the NCCL_LL_THRESHOLD (total threshold) set by user too
+static inline void ncclGetCollResource(ncclComm_t comm, size_t nbytes, int* nrings, int* nthreads, int* ll) {
+  *ll = 0;
+  int llEnforced = 0; /* see if the size falls in the NCCL_LL_THRESHOLD range set by user */
+  if (comm->llThreshold >= 0) { /* user sets total LL threshold */
+    if (nbytes > comm->llThreshold) { /* non-LL */
+      *nthreads = comm->nThreads+1;
+      *nrings = comm->nRings;
+      return;
+    } else {
+      llEnforced = 1; /* user wants to use LL */
+    }
+  }
+  int nt = NCCL_LL_MIN_NTHREADS; /* start with min number of LL threads */
+  size_t nr;
+  int ll_max_nthreads = std::min(NCCL_LL_MAX_NTHREADS, comm->nThreads); /* respect user's setting or platform's default setting */
+  int maxRings = (comm->nRanks <= 4) ? 1 : ll_max_nthreads / NCCL_LL_MIN_NTHREADS;
+  ssize_t threshold = std::min(comm->threadThreshold, (ssize_t)NCCL_LL_RING_THRESHOLD);
+  while (nt < ll_max_nthreads && *ll == 0) {
+    nr = DIVUP(nbytes, (NCCL_LL_RING_THRESHOLD*nt*comm->nRanks));
+    if (nr <= maxRings) { /* avoid using few threads but many rings */
+      nr = nr == 0 ? 1 : nr > comm->nRings ? comm->nRings : nr;
+      *ll = nbytes > comm->nRanks*nr*nt*threshold ? 0 : 1;
+    }
+    if (*ll == 0) {
+      nt = nt << 1;
+    }
+  }
+  if (*ll == 1) {
+    *nthreads = nt;
+    *nrings = (int)nr;
+    return; /* we can use smaller number of threads to make LL work, stop here */
+  }
+  nr = DIVUP(nbytes, (NCCL_LL_RING_THRESHOLD*ll_max_nthreads*comm->nRanks)); /* else we try the max number of LL threads */
+  nr = nr == 0 ? 1 : nr > comm->nRings ? comm->nRings : nr;
+  *ll = nbytes > comm->nRanks*nr*ll_max_nthreads*comm->threadThreshold ? llEnforced : 1;
+  *nthreads = *ll ? ll_max_nthreads : comm->nThreads+1;
+  *nrings = *ll ? (int)nr : comm->nRings;
+}
+
+static ncclResult_t saveKernel(int coll, const void* sendbuff, void* recvbuff, size_t count,
+    ncclDataType_t dtype, ncclRedOp_t op, int root, ncclComm_t comm, cudaStream_t stream, size_t nbytes, int loopFactor) {
+  int llMode, nBlocks, nThreads;
+  ncclGetCollResource(comm, nbytes, &nBlocks, &nThreads, &llMode);
+  comm->myParams->blockDim.x = std::max((int)comm->myParams->blockDim.x, nThreads);
+  if (comm->userStreamSet == false) {
+    comm->userStream = stream;
+    comm->userStreamSet = true;
+  } else if (stream != comm->userStream) {
+    WARN("Error : mixing different streams within a group call is not supported.");
+    return ncclInvalidUsage;
+  }
+  int lastChunkSize = 0;
+  if (llMode == 1) {
+    int sliceSize = NCCL_LL_SLICE_LINES * sizeof(uint64_t) / ncclTypeSize(dtype);
+    const ssize_t loopSize = nBlocks*loopFactor*(ssize_t)sliceSize;
+    lastChunkSize = DIVUP((count-count/loopSize*loopSize), nBlocks*loopFactor);
+    ALIGN_SIZE(lastChunkSize, nThreads*sizeof(uint64_t)/ncclTypeSize(dtype));
+  }
+  for (int bid=0; bid<nBlocks; bid++) {
+    struct ncclRing* ring = comm->rings+(comm->myParams->gridDim.x % comm->nRings);
+    if (ring->collCount == NCCL_MAX_OPS) {
+      WARN("Too many aggregated operations (%d max)", NCCL_MAX_OPS);
+      return ncclInvalidUsage;
+    }
+
+    comm->myParams->gridDim.x++;
+
+    int opIndex = ring->collFifoTail;
+    struct ncclColl* c = ring->collectives+opIndex;
+    volatile uint8_t* activePtr = (volatile uint8_t*)&c->active;
+    while (activePtr[0] != 0) sched_yield();
+
+    struct CollectiveArgs* args = &c->args;
+    args->root = root;
+    args->N = count;
+    args->ThisInput = sendbuff;
+    args->ThisOutput = recvbuff;
+    args->comm = comm->devComm;
+    args->opCount = comm->opCount;
+    args->bid = bid;
+    args->nRings = nBlocks;
+    args->nThreads = nThreads;
+    args->lastChunkSize = lastChunkSize;
+
+    c->nThreads = nThreads;
+    c->funcIndex = FUNC_INDEX(coll, op, dtype, llMode);
+    c->active = 1;
+    opIndex = (opIndex+1)%NCCL_MAX_OPS;
+    c->nextIndex = opIndex;
+    ring->collFifoTail = opIndex;
+    ring->collCount++;
+  }
+  /*if (llMode == 0)*/ comm->opCount++;
+  return ncclSuccess;
+}
+
+extern __global__ void ncclMultiOpKernel (struct ncclColl firstColl);
+
+#endif