Sylvain Jeaugey
299c554dcc
Add LL128 Protocol. Rewrite the topology detection and tree/ring creation (#179). Improve tree performance by sending/receiving from different GPUs. Add model-based tuning to switch between the different algorithms and protocols. Rework P2P/SHM detection in containers (#155, #248). Detect duplicated devices and return an error (#231). Add tuning for GCP
139 regels
3.6 KiB
C
139 regels
3.6 KiB
C
/*************************************************************************
|
|
* Copyright (c) 2016-2019, NVIDIA CORPORATION. All rights reserved.
|
|
*
|
|
* See LICENSE.txt for license information
|
|
************************************************************************/
|
|
|
|
#ifndef NCCL_TOPO_H_
|
|
#define NCCL_TOPO_H_
|
|
|
|
#include "graph.h"
|
|
#include "core.h"
|
|
|
|
#define LOC_WIDTH 5000
|
|
#define PASCAL_NVLINK_WIDTH 18
|
|
#define VOLTA_NVLINK_WIDTH 21
|
|
#define PCI_WIDTH 12 // PCI Gen3 x16
|
|
#define QPI_WIDTH 8
|
|
#define SKL_QPI_WIDTH 12
|
|
#define P9_WIDTH 32
|
|
#define NET_WIDTH 12 // 100Gbit
|
|
|
|
// Intel CPU convert GPU P2P traffic into 64B PCI TLPs, to GPU
|
|
// to GPU traffic consumed more PCI bandwidth.
|
|
#define INTEL_P2P(speed) (speed*9/12)
|
|
#define INTEL_P2P_OVERHEAD(speed) (speed*12/9)
|
|
|
|
#define NCCL_TOPO_NODE_TYPES 6
|
|
#define GPU 0
|
|
#define PCI 1
|
|
#define NVS 2
|
|
#define CPU 3 // Actually NUMA domains
|
|
#define NIC 4
|
|
#define NET 5
|
|
extern const char* topoNodeTypeStr[];
|
|
|
|
#define LINK_LOC 0
|
|
#define LINK_NVL 1
|
|
#define LINK_PCI 2
|
|
#define LINK_QPI 3
|
|
#define LINK_NET 4
|
|
extern const char* topoLinkTypeStr[];
|
|
|
|
struct ncclTopoNode;
|
|
struct ncclTopoLink {
|
|
int type;
|
|
int width;
|
|
struct ncclTopoNode* remNode;
|
|
};
|
|
#define NCCL_TOPO_MAX_LINKS 32
|
|
#define NCCL_TOPO_MAX_HOPS (NCCL_TOPO_MAX_NODES*NCCL_TOPO_NODE_TYPES)
|
|
#define SELECT_PATH 1
|
|
#define SELECT_LAST 2
|
|
|
|
#define NET_GDR_MASK 0x70000000
|
|
|
|
struct ncclTopoLinkList {
|
|
struct ncclTopoLink* list[NCCL_TOPO_MAX_HOPS];
|
|
int count;
|
|
int width;
|
|
int type;
|
|
};
|
|
|
|
struct ncclTopoNode {
|
|
int type;
|
|
int64_t id;
|
|
int rank;
|
|
int nlinks;
|
|
struct ncclTopoLink links[NCCL_TOPO_MAX_LINKS];
|
|
// Pre-computed paths to GPUs and NICs
|
|
struct ncclTopoLinkList* paths[NCCL_TOPO_NODE_TYPES];
|
|
// Used during search
|
|
uint64_t used;
|
|
};
|
|
|
|
struct ncclTopoNodeSet {
|
|
int count;
|
|
struct ncclTopoNode nodes[NCCL_TOPO_MAX_NODES];
|
|
};
|
|
|
|
struct ncclTopoSystem {
|
|
struct ncclTopoNodeSet nodes[NCCL_TOPO_NODE_TYPES];
|
|
int maxSpeed;
|
|
int maxWidth;
|
|
int searchInitDone;
|
|
};
|
|
|
|
static ncclResult_t ncclTopoCreateNode(struct ncclTopoSystem* system, struct ncclTopoNode** node, int type, uint64_t id) {
|
|
for (int i=0; i<system->nodes[type].count; i++) {
|
|
if (system->nodes[type].nodes[i].id == id) {
|
|
*node = system->nodes[type].nodes+i;
|
|
return ncclSuccess;
|
|
}
|
|
}
|
|
if (system->nodes[type].count == NCCL_TOPO_MAX_NODES) {
|
|
WARN("Error : tried to create too many nodes of type %d\n", type);
|
|
return ncclInternalError;
|
|
}
|
|
struct ncclTopoNode* n = system->nodes[type].nodes+system->nodes[type].count;
|
|
system->nodes[type].count++;
|
|
n->type = type;
|
|
n->id = id;
|
|
if (type == GPU) {
|
|
// Create link to itself (used in some corner cases)
|
|
n->nlinks=1;
|
|
n->links[0].type = LINK_LOC;
|
|
n->links[0].remNode = n;
|
|
n->links[0].width = LOC_WIDTH;
|
|
}
|
|
*node = n;
|
|
return ncclSuccess;
|
|
}
|
|
|
|
static ncclResult_t ncclTopoConnectNodes(struct ncclTopoNode* node, struct ncclTopoNode* remNode, int type, int width) {
|
|
// Aggregate links into higher width for NVLink
|
|
struct ncclTopoLink* link;
|
|
for (link = node->links; link->remNode; link++) {
|
|
if (link->remNode == remNode && link->type == type) break;
|
|
}
|
|
if (link->remNode == NULL) node->nlinks++;
|
|
link->type = type;
|
|
link->remNode = remNode;
|
|
link->width += width;
|
|
|
|
// Sort links in BW descending order
|
|
struct ncclTopoLink linkSave;
|
|
memcpy(&linkSave, link, sizeof(struct ncclTopoLink));
|
|
while (link != node->links) {
|
|
if ((link-1)->width >= linkSave.width) break;
|
|
memcpy(link, link-1, sizeof(struct ncclTopoLink));
|
|
link--;
|
|
}
|
|
memcpy(link, &linkSave, sizeof(struct ncclTopoLink));
|
|
return ncclSuccess;
|
|
}
|
|
|
|
ncclResult_t ncclTopoPrintPaths(struct ncclTopoSystem* system);
|
|
|
|
#endif
|