whn09 81aee64ac2 neuron: low-latency completion off by default; rank timeline (DEEPINFER_NEURON_RANK_TIMELINE) and Engram prefault
The runtime's low-latency completion thread busy-polls the notification queues (~0.7 CPU per process). With 64
ranks on one host the run queue reached ~470 tasks on 192 CPUs at step boundaries; main threads were preempted
(Engram gather 3 ms CPU in 15 ms wall), and a different rank paced the collectives every step.
NEURON_RT_XU_WORKER_ENABLE_LOW_LATENCY_COMPLETION=0: decode step 580 -> 522 ms, TPOT 204.5 -> 184.2 ms,
TTFT 1.60 -> 1.52 s (vllm-sonnet 512, bucket 512), tokens unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-27 22:24:34 +08:00
..
eplb initial commit 2026-10-20 12:09:42 +08:00
input_metadata initial commit 2026-10-20 12:09:42 +08:00
layers neuron: fp8-activation linears take the NKI kernel (Engram projection); drop unused fp8 hidden copies before region splits; log weights without NKI scales 2026-10-27 11:50:34 +08:00
models neuron: low-latency completion off by default; rank timeline (DEEPINFER_NEURON_RANK_TIMELINE) and Engram prefault 2026-10-27 22:24:34 +08:00
parallel_utils initial commit 2026-10-20 12:09:42 +08:00
__init__.py initial commit 2026-10-20 12:09:42 +08:00
layer_utils.py initial commit 2026-10-20 12:09:42 +08:00
model_loader.py neuron: shared expert sliced over ranks, summed in the MoE all-reduce (DEEPINFER_NEURON_SHARED_SLICE=1) 2026-10-27 01:31:41 +08:00
model_metadata_utils.py Neuron: prompt chunks through the decode region graphs (issue #26) 2026-10-23 03:19:56 +08:00
model_output.py initial commit 2026-10-20 12:09:42 +08:00
sampling_inputs.py initial commit 2026-10-20 12:09:42 +08:00
utils.py Neuron: static decode graphs, static-shape MoE, trn2 e4m3 fp8 (issues #9, #12, #24) 2026-10-22 11:59:37 +08:00