Add scalable init API
 * Add new ncclCommInitRankScalable to allow for passing multiple
   unique IDs to the init function.
 * Spreads the load onto multiple bootstrap roots, allowing for
   constant bootstrap time.
 * Requires multiple ranks to create a unique ID, and the CPU-side
   ID exchange code to call allgather[v] instead of broadcast.

Accelerate init bootstrap operations
 * Reduce the number of calls to allgather.
 * Allow roots to reply early to ranks when information is already
   available.
 * Add an option to use ncclNet instead of sockets to perform
   bootstrap allgather operations.

Add PAT algorithms for Allgather and ReduceScatter
 * Parallel Aggregated Trees, variation of Bruck algorithm.
 * Logarithmic number of network steps for small sizes at scale.
 * Only supports one rank per node at the moment.

Add support for registered buffers for intra-node communication.
 * Allow registered user buffers to be accessed directly intra-node
 * Avoids extra copies in algorithms which permit it, saving
   memory bandwidth and helping with compute overlap.

Add profiler plugin API
 * New plugin API for profiling
 * Supports various levels of profiling, with a hierarchy.

Asynchronous graph allocation
 * Make calls to cudaMalloc and cudaMemcpy during graph allocation
   asynchronous.
 * Significantly speeds up graph capture.

Use fatal IB asynchronous events to stop network operation
 * Avoids many other error messages
 * Only fatal errors are affected; potentially transient errors
   (e.g. port down) do not cause an immediate stop.

Set P2P level to PXB on AMD CPUs when using more than 2 GPUs per node
 * P2P would cause a significant performance degradation when using
   many GPUs, and therefore many interleaved data flows.
 * Disable P2P through the CPU when we have 3+ GPUs per node; keep it
   enabled when we only have 2 GPUs.

Improve the init logs to report the real NCCL function.
 * Make the log report ncclCommInitRank or ncclCommSplit, rather than
   the generic ncclCommInitRankFunc.

Add a parameter to set the location of the user configuration file.
 * Add NCCL_CONF_FILE environment variable to set where the user's
   configuration file resides.

Increase default IB timeout
 * Increase IB timeout value from 18 to 20.
 * Should help avoid fatal errors on large RoCE systems.

Add new check for nvidia peermem
 * On linux kernels 6.6+, /sys/kernel/mm/memory_peers is no longer
   present; check for /sys/module/nvidia_peermem/version instead.

Fix old performance regression when mixing small and large operations.
 * Improves distribution of work on channels.

Fix crash when NUMA IDs are equal to -1.
 * Can happen when a NIC is a virtual NIC, or when linux doesn't
   know which NUMA node a device is attached to
 * Issue NVIDIA/nccl-tests#233

Fix tree graph search when NCCL_CROSS_NIC is set to 1.
 * Would force NCCL to use the balanced_tree pattern, thereby
   disabling LL128 on platforms with 1 GPU+1 NIC per PCI switch.
 * Would also try to use alternate rings even though it was not
   needed.

Compiler tweaks and fixes
 * PR #1177
 * PR #1228

Fix stack smash
 * PR #1325

Fixes for multi-node NVLink + IB operation

Coverity fixes and comments.


[ROCm/rccl commit: 68b542363f]
This commit is contained in:
Sylvain Jeaugey
2024-09-10 05:57:10 -07:00
bovenliggende 5ca1b6c160
commit 60240fec77
88 gewijzigde bestanden met toevoegingen van 7119 en 1965 verwijderingen
+4 -3
Bestand weergeven
@@ -33,13 +33,14 @@ ncclResult_t ncclTopoComputeCommCPU(struct ncclComm* comm);
// Query topology
ncclResult_t ncclTopoGetNetDev(struct ncclComm* comm, int rank, struct ncclTopoGraph* graph, int channelId, int peerRank, int64_t* id, int* dev, int* proxyRank);
ncclResult_t ncclTopoCheckP2p(struct ncclTopoSystem* system, int64_t id1, int64_t id2, int* p2p, int *read, int* intermediateRank);
ncclResult_t ncclTopoCheckP2p(struct ncclTopoSystem* system, int rank1, int rank2, int* p2p, int *read, int* intermediateRank);
ncclResult_t ncclTopoCheckMNNVL(struct ncclTopoSystem* system, struct ncclPeerInfo* info1, struct ncclPeerInfo* info2, int* ret);
ncclResult_t ncclTopoCheckGdr(struct ncclTopoSystem* topo, int64_t busId, int64_t netId, int read, int* useGdr);
ncclResult_t ncclTopoNeedFlush(struct ncclTopoSystem* system, int64_t busId, int* flush);
ncclResult_t ncclTopoCheckNet(struct ncclTopoSystem* system, int64_t id1, int64_t id2, int* net);
ncclResult_t ncclTopoCheckNet(struct ncclTopoSystem* system, int rank1, int rank2, int* net);
int ncclPxnDisable(struct ncclComm* comm);
ncclResult_t ncclTopoGetPxnRanks(struct ncclComm* comm, int** intermediateRanks, int* nranks);
ncclResult_t ncclGetLocalCpu(struct ncclTopoSystem* system, int gpu, int* retCpu);
// Find CPU affinity
ncclResult_t ncclTopoGetCpuAffinity(struct ncclTopoSystem* system, int rank, cpu_set_t* affinity);
@@ -76,7 +77,7 @@ ncclResult_t ncclTopoSearchInit(struct ncclTopoSystem* system);
#define NCCL_TOPO_PATTERN_COLLNET_DIRECT 6 // Collnet Direct
struct ncclTopoGraph {
// Input / output
int id; // ring : 0, tree : 1, collnet : 2
int id; // ring : 0, tree : 1, collnet : 2, nvls : 3, collnetDirect : 4
int pattern;
int crossNic;
int collNet;