NCCL 2.26.3-1

Minimize the performance impact of the device kernel profiling support when
the profiler plugin is not loaded.

Reduce the overheads of CUDA graph capturing, which increased in NCCL
2.26.2 for large graphs.

Fix the exchange of enhanced connection establishment (ECE) options to
address potential slowdowns on networks utilizing RoCE.

Test if cuMem host allocations work and if not, disable them. Enabled by
default since NCCL 2.24 if the CUDA driver version is at least 12.6, such
allocations rely on NUMA support, which is by default not available under
Docker. We recommend invoking Docker with "--cap-add SYS_NICE" to enable
it.

Fix an initialization error when running with NCCL_NET_GDR_C2C=1 on
multiple MNNVL domains with non-uniform network configurations across
nodes.

Fix the printing of sub-seconds in the debug log when using a custom
NCCL_DEBUG_TIMESTAMP_FORMAT setting.
This commit is contained in:
Kamil Iskra
2025-04-22 13:50:40 -07:00
parent 145e67e707
commit 0524aef7a0
17 changed files with 182 additions and 34 deletions
+6
View File
@@ -88,6 +88,12 @@ struct ncclProxyOp {
struct ncclTaskP2p* p2p;
} task;
// Profiler work counter increment flag. Set to 'true' if the profiler work counter for this channel needs increment.
// Always 'true' for collective operations. Grouped p2p operations are fused into one <send, recv> pair in the GPU kernel,
// meaning the GPU profiler code increments the work counter for the pair rather than the individual p2p. For this
// reason, the incWorkCounter flag is used to avoid incrementing the work counter twice in the host code. This is done
// by setting incWorkCounter to 'true' only for one of the p2ps in the pair during enqueue.
bool incWorkCounter;
int eActivationMask;
void* taskEventHandle;
int rank;